Add panic after continuing storage iteration after a storage mutation

[dsainati1]

Closes #208

Because modifying storage can arbitrarily rearrange the way that values are stored within it, we want to prevent users from iterating over a mutated storage. Thus, if users continue a storage iteration after performing a mutating operation, we will panic and abort execution. If users end iteration after their mutation however, this is safe, as no operations are performed that rely on the stored values maintaining their original, pre-mutation, arrangement.

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• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[codecov]

Codecov Report

Merging #1892 (8ab6195) into master (38e80fb) will increase coverage by 0.22%.
The diff coverage is 92.85%.

❗ Current head 8ab6195 differs from pull request most recent head 7eea70e. Consider uploading reports for the commit 7eea70e to get more accurate results

@@            Coverage Diff             @@
##           master    #1892      +/-   ##
==========================================
+ Coverage   77.65%   77.87%   +0.22%     
==========================================
  Files         302      300       -2     
  Lines       61976    62239     +263     
==========================================
+ Hits        48126    48470     +344     
+ Misses      12128    12050      -78     
+ Partials     1722     1719       -3     

Flag	Coverage Δ
unittests	77.87% <92.85%> (+0.22%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
runtime/interpreter/errors.go	26.94% <0.00%> (-0.25%)	⬇️
runtime/interpreter/interpreter.go	89.70% <100.00%> (+0.70%)	⬆️
runtime/interpreter/storage.go	69.04% <0.00%> (-1.59%)	⬇️
runtime/environment.go	88.96% <0.00%> (-0.18%)	⬇️
runtime/interpreter/interpreter_statement.go	91.79% <0.00%> (-0.09%)	⬇️
runtime/repl.go	0.00% <0.00%> (ø)
runtime/stackdepth.go
runtime/interpreter/sharedstate.go
runtime/ast/expression.go	88.82% <0.00%> (+0.35%)	⬆️
runtime/interpreter/value.go	72.14% <0.00%> (+0.42%)	⬆️
... and 6 more

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[github-actions]

Cadence Benchstat comparison

This branch with compared with the base branch onflow:master commit a22f767
The command for i in {1..N}; do go test ./... -run=XXX -bench=. -benchmem -shuffle=on; done was used.
Bench tests were run a total of 7 times on each branch.

Collapsed results for better readability

	old.txt	new.txt
	time/op		delta
CheckContractInterfaceFungibleTokenConformance-2	169µs ± 3%	167µs ± 1%	~	(p=0.310 n=6+6)
ContractInterfaceFungibleToken-2	46.8µs ± 3%	48.7µs ±10%	~	(p=0.073 n=7+7)
InterpretRecursionFib-2	3.00ms ± 2%	3.03ms ± 3%	~	(p=0.445 n=6+7)
NewInterpreter/new_interpreter-2	1.28µs ± 1%	1.31µs ± 2%	~	(p=0.147 n=6+7)
NewInterpreter/new_sub-interpreter-2	808ns ± 2%	811ns ± 3%	~	(p=0.836 n=7+6)
ParseArray-2	9.75ms ± 2%	10.04ms ± 6%	~	(p=0.295 n=6+7)
ParseDeploy/byte_array-2	15.0ms ± 6%	14.8ms ± 2%	~	(p=1.000 n=7+6)
ParseDeploy/decode_hex-2	1.39ms ± 4%	1.37ms ± 3%	~	(p=0.805 n=7+7)
ParseFungibleToken/With_memory_metering-2	239µs ± 6%	239µs ± 2%	~	(p=0.710 n=7+7)
ParseFungibleToken/Without_memory_metering-2	181µs ± 3%	184µs ± 5%	~	(p=0.383 n=7+7)
ParseInfix-2	8.51µs ± 2%	8.38µs ± 1%	~	(p=0.073 n=7+7)
QualifiedIdentifierCreation/One_level-2	3.19ns ± 2%	3.16ns ± 0%	~	(p=0.111 n=7+6)
QualifiedIdentifierCreation/Three_levels-2	163ns ± 1%	165ns ± 3%	~	(p=0.219 n=7+7)
RuntimeFungibleTokenTransfer-2	936µs ± 5%	776µs ±29%	~	(p=0.073 n=6+7)
RuntimeResourceDictionaryValues-2	5.88ms ± 4%	5.86ms ± 5%	~	(p=0.805 n=7+7)
RuntimeScriptNoop-2	28.6µs ±12%	22.8µs ±34%	~	(p=0.138 n=6+7)
ValueIsSubtypeOfSemaType-2	105ns ± 4%	105ns ± 9%	~	(p=0.782 n=7+7)
	alloc/op		delta
CheckContractInterfaceFungibleTokenConformance-2	62.0kB ± 0%	62.0kB ± 0%	~	(all equal)
ContractInterfaceFungibleToken-2	24.3kB ± 0%	24.3kB ± 0%	~	(p=1.000 n=7+7)
InterpretRecursionFib-2	1.23MB ± 0%	1.23MB ± 0%	~	(p=1.000 n=6+6)
NewInterpreter/new_interpreter-2	832B ± 0%	848B ± 0%	+1.92%	(p=0.001 n=7+7)
NewInterpreter/new_sub-interpreter-2	312B ± 0%	312B ± 0%	~	(all equal)
ParseArray-2	2.77MB ± 0%	2.80MB ± 2%	~	(p=0.366 n=6+7)
ParseDeploy/byte_array-2	4.49MB ± 4%	4.55MB ± 0%	~	(p=0.530 n=7+5)
ParseDeploy/decode_hex-2	214kB ± 0%	214kB ± 0%	~	(p=0.774 n=7+7)
ParseFungibleToken/With_memory_metering-2	36.3kB ± 0%	36.3kB ± 0%	~	(p=0.110 n=7+7)
ParseFungibleToken/Without_memory_metering-2	36.3kB ± 0%	36.3kB ± 0%	~	(p=0.898 n=7+7)
ParseInfix-2	2.17kB ± 0%	2.17kB ± 0%	~	(p=0.592 n=7+7)
QualifiedIdentifierCreation/One_level-2	0.00B	0.00B	~	(all equal)
QualifiedIdentifierCreation/Three_levels-2	64.0B ± 0%	64.0B ± 0%	~	(all equal)
RuntimeFungibleTokenTransfer-2	116kB ± 1%	116kB ± 1%	~	(p=0.097 n=7+7)
RuntimeResourceDictionaryValues-2	2.27MB ± 0%	2.27MB ± 0%	~	(p=0.710 n=7+7)
RuntimeScriptNoop-2	9.24kB ± 0%	9.25kB ± 0%	~	(p=0.515 n=7+7)
ValueIsSubtypeOfSemaType-2	48.0B ± 0%	48.0B ± 0%	~	(all equal)
	allocs/op		delta
CheckContractInterfaceFungibleTokenConformance-2	1.03k ± 0%	1.03k ± 0%	~	(all equal)
ContractInterfaceFungibleToken-2	428 ± 0%	428 ± 0%	~	(all equal)
InterpretRecursionFib-2	22.5k ± 0%	22.5k ± 0%	~	(all equal)
NewInterpreter/new_interpreter-2	14.0 ± 0%	14.0 ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	6.00 ± 0%	6.00 ± 0%	~	(all equal)
ParseArray-2	70.0k ± 0%	70.0k ± 0%	~	(p=0.303 n=5+7)
ParseDeploy/byte_array-2	105k ± 0%	105k ± 0%	~	(p=0.780 n=7+7)
ParseDeploy/decode_hex-2	77.0 ± 0%	77.0 ± 0%	~	(all equal)
ParseFungibleToken/With_memory_metering-2	1.06k ± 0%	1.06k ± 0%	~	(all equal)
ParseFungibleToken/Without_memory_metering-2	1.06k ± 0%	1.06k ± 0%	~	(all equal)
ParseInfix-2	66.0 ± 0%	66.0 ± 0%	~	(all equal)
QualifiedIdentifierCreation/One_level-2	0.00	0.00	~	(all equal)
QualifiedIdentifierCreation/Three_levels-2	2.00 ± 0%	2.00 ± 0%	~	(all equal)
RuntimeFungibleTokenTransfer-2	2.26k ± 0%	2.26k ± 0%	~	(p=0.245 n=6+7)
RuntimeResourceDictionaryValues-2	36.9k ± 0%	36.9k ± 0%	~	(p=0.564 n=7+6)
RuntimeScriptNoop-2	149 ± 0%	149 ± 0%	~	(all equal)
ValueIsSubtypeOfSemaType-2	1.00 ± 0%	1.00 ± 0%	~	(all equal)

[turbolent]

Nice! This is going to make the iteration feature even more useful and ergonomic 👍

[turbolent]

👍