Nightly release - add changelog since last release

.github/workflows/build.yml

@@ -1,3 +1,5 @@
+name: WLED Build
+
 # Only included into other workflows
 on:
   workflow_call:

.github/workflows/nightly.yml

@@ -26,8 +26,7 @@ jobs:
         uses: janheinrichmerker/action-github-changelog-generator@v2.3
         with:
           token: ${{ secrets.GITHUB_TOKEN }} 
-          sinceTag: nightly
-          onlyLastTag: true
+          sinceTag: v0.15.0
       - name: Update Nightly Release
         uses: andelf/nightly-release@main
         env: