chore: Update fetch-depth comment (#408)

Author: keelerm84

.github/workflows/release-please.yml

@@ -22,7 +22,7 @@ jobs:
       - uses: actions/checkout@v4
         if: ${{ steps.release.outputs.releases_created == 'true' }}
         with:
-          fetch-depth: 0 # If you only need the current version keep this.
+          fetch-depth: 0 # Full history is required for proper changelog generation
 
       - uses: actions/setup-python@v5
         if: ${{ steps.release.outputs.releases_created == 'true' }}