As a software engineer
I want to remove unused test dependencies
So that there aren't warnings or test failures when cargo test is ran

Given lib.rs is giving false positives for test warnings
When fixing test warnings
Then add the following to the top of /src/lib.rs: `#![cfg_attr(test, allow(unused_imports, unused_variables, dead_code))]`
And because child mods then unnecessarily inherit this cfg_attr, add the following to the top of every child mod.rs, to add warnings again: `#![cfg_attr(test, warn(unused_imports, unused_variables, dead_code))]`
And do this first, before fixing the remaining warnings below

Given the tests within 'mod tests' have a different set of required dependencies
When fixing `warning: unused imports:` in cargo test
Then remove the associated line of code in the warning message
And only remove imports within `mod tests` blocks

Given the tests within 'mod tests' sometimes have stale variables
When fixing `warning: unused variable:` in cargo test
Then remove the associated line of code in the warning message
And only remove unused code within `mod tests` blocks

Implementation Notes

- Place any unit tests at the bottom of the same file as the associated production code
- Increment patch version of anttp package in Cargo.toml
- Create a copy of this issue description and save to /spec using the name of this issue as the filename (with lower underscore case, starting with the 5 char padded issue number, e.g. 00001_issue_title.txt)
- Ensure cargo build and cargo test still pass
- Ensure NO cargo build errors occur
- DO NOT change lib.rs, other than adding the `cfg_attr` highlighted above. 
