docs: add changelog for #3559

Author: iBotPeaches

docs/unreleased.mdx

@@ -9,6 +9,7 @@ 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)
+- [[#3559](https://github.com/iBotPeaches/Apktool/pull/3559)] Add reproducible builds (drop Proguard for R8).
 - [[#3512](https://github.com/iBotPeaches/Apktool/issues/3512)] Fix disassembly of Facebook.
 - [[#3536](https://github.com/iBotPeaches/Apktool/issues/3536)] Fix treating `stamp-cert-sha256` as unknown file.
 - [[#3519](https://github.com/iBotPeaches/Apktool/pull/3519)] Upgrade baksmali/smali to `3.0.5`.