Silence some warnings from derive(Properties)

[WorldSEnder]

Description

The derive macro for Properties should preserve some attributes on fields.

On the one hand, warnings on setters and fields of the generated builder are reported on the original field due to spanned quotes. It can be confusing to users that adding silencing annotations have no effect before this patch.

On the other hand, cfg attributes are passed on to work around an issue with rust-analyzer; Normally cfg attributes are evaluated by the compiler before the token tree is passed to the proc-macro. rust-analyzer seems not to do that in some cases, but still generates errors and lints based on the result. When trying to connect those errors back to the source code, it reports "no-such-field" since cfg attributes on the original struct are respect and the field is invisible.
To be clear, cfg attributes are not expected to show up during normal compilation, but are a quirk in some IDEs. In any case, it shouldn't hurt to respect them if they are found.

Checklist

• I have run cargo make pr-flow
• I have reviewed my own code
• I have added tests

[WorldSEnder]

I have difficulties replicating this in a test case since I don't know how trybuild can be made to run clippy lints and reproducing an IDE setup to run rust-analyzer is also not an accessible goal for me.

[hamza1311]

#[allow(_)] and #[deny(_)] work with cargo lints too. If possible, we should add test cases for those. I don't know if #[cfg(_)] can be tested though

[voidpumpkin]

LGTM
Thank you for the PR!

[WorldSEnder]

My pleasure 👍

[hamza1311]

LGTM