Pin Gradle Version

Ran into errors which were unexpected. `baseName` needed to become `archiveBaseName` in build.gradle ... this is because the github action just uses the latest version of gradle, and that is not pinned.

先閱讀 build.gradle，並檢查 GitHub Action 如何選擇 Gradle 版本。確認哪個版本與現有 build 相容，固定該版本，並驗證回報的 baseName/archiveBaseName 錯誤不再發生。

由索引模型根據 Issue 內容生成。