maint: Add exclusion feature to `fixup-features`

This commit adds an --exclude <PREFIX> argument to the fixup-features tool in order to ignore crate paths for crates that we do not publish, mainly those in the examples/ and maint/ directory.

Fixes #1766 (closed)

doc/dev/Release.md

@@ -50,7 +50,7 @@ to make sure we aren't going to break our users.
    Note: fixup-features should be run with the top-level Cargo.toml
    as an argument:
    ```
-   cargo run -p fixup-features Cargo.toml
+   cargo run -p fixup-features -- --exclude examples/ --exclude maint/ Cargo.toml
    ```
 
 6. Does `maint/semver-checks "arti-v$LAST_VERSION"` find any issues

[opara]

I think it would be helpful to also document this flag in the "To use" section of the docs in maint/fixup-features/src/main.rs.

[opara]

I think it should also be documented somewhere that this compares the strings to the workspace member strings and not the paths, so that someone doesn't use --exclude ./examples/ or something similar.

[Clara Engler]

The --help overview says <PREFIX1> and <PREFIX2>. I am not sure if this is enough for implying that it is string based though, but personally I interpret anything that is not <PATH> or <FILE> as something string based.

Maybe <PATTERN> is a good alternative though?

[opara]

Okay, I think PREFIX is better than PATTERN here. I'm of the opinion that more documentation is always better :)