Implement std::error::Error for GcObject borrow errors

[HalidOdat]

It changes the following:

• Implement std::error::Error for BorrowError and BorrowMutErrror

[codecov]

Codecov Report

Merging #662 into master will not change coverage.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master     #662   +/-   ##
=======================================
  Coverage   72.69%   72.69%           
=======================================
  Files         179      179           
  Lines       13409    13409           
=======================================
  Hits         9748     9748           
  Misses       3661     3661           

Impacted Files	Coverage Δ
boa/src/builtins/object/gcobject.rs	73.87% <0.00%> (ø)

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[github-actions]

Benchmark for 2fe1de6

Click to view benchmark

Test	PR Benchmark	Master Benchmark	%
Arithmetic operations (Execution)	282.1±25.60ns	274.9±13.46ns	+2.62%
Arithmetic operations (Full)	195.6±15.76µs	188.6±17.59µs	+3.71%
Array access (Execution)	6.2±0.55µs	6.1±0.35µs	+1.64%
Array access (Full)	202.2±8.51µs	200.3±9.46µs	+0.95%
Array creation (Execution)	2.6±0.17ms	2.6±0.14ms	0.00%
Array creation (Full)	2.8±0.11ms	2.9±0.17ms	-3.45%
Array pop (Execution)	916.2±42.54µs	915.5±40.96µs	+0.08%
Array pop (Full)	1239.0±78.92µs	1210.6±66.47µs	+2.35%
Boolean Object Access (Execution)	3.6±0.23µs	3.6±0.24µs	0.00%
Boolean Object Access (Full)	196.8±10.64µs	201.5±13.46µs	-2.33%
Clean js (Execution)	572.6±37.27µs	567.0±37.82µs	+0.99%
Clean js (Full)	791.0±59.84µs	767.1±42.13µs	+3.12%
Clean js (Parser)	18.3±0.96µs	18.4±1.03µs	-0.54%
Create Realm	351.2±22.33ns	369.1±29.94ns	-4.85%
Dynamic Object Property Access (Execution)	4.0±0.25µs	4.0±0.28µs	0.00%
Dynamic Object Property Access (Full)	198.6±10.40µs	199.0±12.59µs	-0.20%
Expression (Lexer)	1805.2±132.44ns	1777.5±89.42ns	+1.56%
Expression (Parser)	4.1±0.29µs	4.1±0.27µs	0.00%
Fibonacci (Execution)	613.8±39.37µs	600.9±31.54µs	+2.15%
Fibonacci (Full)	836.5±105.23µs	815.3±37.98µs	+2.60%
For loop (Execution)	16.8±1.09µs	16.5±0.63µs	+1.82%
For loop (Full)	212.6±13.54µs	210.9±11.64µs	+0.81%
For loop (Lexer)	3.2±0.19µs	3.3±0.24µs	-3.03%
For loop (Parser)	9.4±0.58µs	9.5±0.55µs	-1.05%
Goal Symbols (Parser)	6.4±0.39µs	6.4±0.36µs	0.00%
Hello World (Lexer)	641.1±38.17ns	652.9±39.17ns	-1.81%
Hello World (Parser)	1660.5±93.12ns	1681.9±98.42ns	-1.27%
Long file (Parser)	4.8±0.19ms	4.8±0.16ms	0.00%
Mini js (Execution)	521.0±35.26µs	507.3±27.20µs	+2.70%
Mini js (Full)	713.7±34.22µs	717.0±51.54µs	-0.46%
Mini js (Parser)	16.8±1.06µs	16.9±1.21µs	-0.59%
Number Object Access (Execution)	2.8±0.16µs	2.9±0.21µs	-3.45%
Number Object Access (Full)	201.8±20.44µs	193.1±9.53µs	+4.51%
Object Creation (Execution)	3.4±0.22µs	3.5±0.28µs	-2.86%
Object Creation (Full)	237.8±15.87µs	235.3±12.17µs	+1.06%
RegExp (Execution)	49.8±2.83µs	49.9±3.14µs	-0.20%
RegExp (Full)	319.3±22.81µs	319.4±29.17µs	-0.03%
RegExp Literal (Execution)	52.8±3.95µs	52.8±3.20µs	0.00%
RegExp Literal (Full)	249.2±10.71µs	254.4±15.18µs	-2.04%
RegExp Literal Creation (Execution)	49.4±2.13µs	50.7±3.62µs	-2.56%
RegExp Literal Creation (Full)	313.7±22.44µs	307.2±17.84µs	+2.12%
Static Object Property Access (Execution)	3.6±0.24µs	3.6±0.22µs	0.00%
Static Object Property Access (Full)	198.4±11.57µs	199.8±11.67µs	-0.70%
String Object Access (Execution)	5.2±0.41µs	5.2±0.36µs	0.00%
String Object Access (Full)	201.3±13.51µs	199.7±13.13µs	+0.80%
String comparison (Execution)	4.9±0.41µs	4.8±0.34µs	+2.08%
String comparison (Full)	202.7±13.94µs	208.4±18.14µs	-2.74%
String concatenation (Execution)	3.8±0.20µs	3.9±0.37µs	-2.56%
String concatenation (Full)	195.7±11.36µs	200.6±13.71µs	-2.44%
String copy (Execution)	2.8±0.15µs	2.8±0.17µs	0.00%
String copy (Full)	200.3±16.17µs	195.6±17.17µs	+2.40%
Symbols (Execution)	2.4±0.26µs	2.4±0.21µs	0.00%
Symbols (Full)	185.9±20.98µs	178.8±8.51µs	+3.97%

[Razican]

Looks good, thanks!