Fix manual publishing

Author: adpi2

.github/workflows/manual-release.yml

@@ -26,7 +26,7 @@ jobs:
       shell: bash
   publish:
     if: startsWith(github.ref, 'refs/tags/v')
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     env:
       SCALA_VERSION: ${{ inputs.scala-version }}
       PGP_PASSPHRASE: ${{ secrets.PGP_PASSPHRASE }}