add auto-tune and auto-bail

[epi052]

• closes [FEATURE REQUEST] Detect excessive 403s  #200
• closes [FEATURE REQUEST] Dynamically tuning concurrency/connection limit or bailing after n connection failures #123
• closes Bump env_logger from 0.8.2 to 0.8.3 #217

Branching checklist

• There is an issue associated with your PR (bug, feature, etc.. if not, create one)
• Your PR description references the associated issue (i.e. fixes #123456)
• Code is in its own branch
• Branch name is related to the PR contents
• PR targets master

Static analysis checks

• All rust files are formatted using cargo fmt
• All clippy checks pass when running cargo clippy --all-targets --all-features -- -D warnings -A clippy::deref_addrof
• All existing tests pass

Documentation

• New code is documented using doc comments
• Documentation about your PR is included in the README, as needed

Additional Tests

• New code is unit tested
• New code is integration tested, as needed
• New tests pass

[codecov]

Codecov Report

Merging #212 (bd4f602) into master (ec1a20c) will decrease coverage by 0.28%.
The diff coverage is 91.78%.

@@            Coverage Diff             @@
##           master     #212      +/-   ##
==========================================
- Coverage   94.37%   94.09%   -0.29%     
==========================================
  Files          50       53       +3     
  Lines        4585     4994     +409     
==========================================
+ Hits         4327     4699     +372     
- Misses        258      295      +37     

Impacted Files	Coverage Δ
src/event_handlers/outputs.rs	99.18% <ø> (ø)
src/event_handlers/statistics.rs	98.68% <ø> (ø)
src/main.rs	94.44% <ø> (ø)
src/statistics/error.rs	0.00% <ø> (ø)
src/statistics/field.rs	0.00% <ø> (ø)
src/scan_manager/scan_container.rs	77.43% <81.48%> (+0.54%)	⬆️
src/scanner/utils.rs	87.82% <87.82%> (ø)
src/scanner/container.rs	91.17% <91.17%> (ø)
src/scanner/tests.rs	91.66% <91.66%> (ø)
src/scanner/init.rs	94.11% <94.11%> (ø)
... and 18 more

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