💅 Address all instances of BytesWarning

[webknjaz]

Things like byte-to-int comparisons and interpolation of bytes into str were present in the code base. This patch fixes that by making sure that the variables are always of compatible types in these cases.

❓ What kind of change does this PR introduce?

• 🐞 bug fix
• 🐣 feature
• 📋 docs update
• 📋 tests/coverage improvement
• 📋 refactoring
• 💥 other

📋 What is the related issue number (starting with #)

N/A

❓ What is the current behavior? (You can also link to an open issue here)

Currently, a BytesWarning is emitted. Mostly in tests, but there's one place where it's happening in the HTTP parser too.

❓ What is the new behavior (if this is a feature change)?

BytesWarning no more!

📋 Other information:

N/A

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  the changes have been approved
• Unit tests for the changes exist
• Integration tests for the changes exist (if applicable)
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• The new code doesn't generate linter offenses
• Documentation reflects the changes
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  and description in grammatically correct, complete sentences

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