build(deps): update proc-macro-crate requirement from 2.0 to 3.0

Updates the requirements on [proc-macro-crate](https://github.com/bkchr/proc-macro-crate) to permit the latest version.
- [Release notes](https://github.com/bkchr/proc-macro-crate/releases)
- [Commits](bkchr/proc-macro-crate@v2.0.0...v2.0.1)

---
updated-dependencies:
- dependency-name: proc-macro-crate
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

gtk4-macros/Cargo.toml

@@ -22,7 +22,7 @@ blueprint = []
 [dependencies]
 anyhow = "1.0"
 quick-xml = {version = "0.31", optional = true}
-proc-macro-crate = "2.0"
+proc-macro-crate = "3.0"
 proc-macro-error = "1.0"
 proc-macro2 = "1.0"
 quote = "1.0"