docs: add changelog for #3509

Author: iBotPeaches

docs/unreleased.mdx

@@ -10,5 +10,6 @@ The changelog of the upcoming release, subject to change prior to finalization.
 
 - [[#3476](https://github.com/iBotPeaches/Apktool/pull/3476)] Add parallelization to `build` command. (Thanks Cregrant)
 - [[#3459](https://github.com/iBotPeaches/Apktool/pull/3459)] Upgrade Gradle to `8.5`. (Thanks ArjunaKumarMohanta)
+- [[#3509](https://github.com/iBotPeaches/Apktool/pull/3509)] Upgrade `proguard-gradle` to `7.4.2`.
 - [[#3470](https://github.com/iBotPeaches/Apktool/pull/3470), [#3479](https://github.com/iBotPeaches/Apktool/pull/3479), [#3500](https://github.com/iBotPeaches/Apktool/pull/3500)] Upgrade `gradle/gradle-build-action` to `2.12.0`.
 - [[#3471](https://github.com/iBotPeaches/Apktool/pull/3471)] Upgrade `github/codeql-action` to `3`.