night build script updates

Fixes some deprecation warnings during nightly build runs. Already tested in WLED-MM.
* upgrade action-github-changelog-generator to 2.4
* decode changelog into a temporary file (needed for changelog-generator 2.4)
* renamed exclude-labels (deprecated); added some more tags for filtering

.github/workflows/nightly.yml

@@ -23,12 +23,13 @@ jobs:
         run: ls -la
       - name: "✏️ Generate release changelog"
         id: changelog
-        uses: janheinrichmerker/action-github-changelog-generator@v2.3
+        uses: janheinrichmerker/action-github-changelog-generator@v2.4
         with:
           token: ${{ secrets.GITHUB_TOKEN }} 
           sinceTag: v0.15.0
+          output: CHANGELOG_NIGHTLY.md
           # Exclude issues that were closed without resolution from changelog
-          exclude-labels: 'stale,wontfix,duplicate,invalid'
+          excludeLabels: 'stale,wontfix,duplicate,invalid,question,use-as-is,not_planned'
       - name: Update Nightly Release
         uses: andelf/nightly-release@main
         env:
@@ -37,7 +38,7 @@ jobs:
           tag_name: nightly
           name: 'Nightly Release $$'
           prerelease: true
-          body: ${{ steps.changelog.outputs.changelog }}
+          body_path: CHANGELOG_NIGHTLY.md
           files: |
             *.bin
             *.bin.gz