fix: revert max parallel jobs to 1 in Docker publish workflow

Author: pablodz

.github/workflows/docker-publish.yml

@@ -8,8 +8,7 @@ jobs:
   build-and-push:
     runs-on: ubuntu-latest
     strategy:
-      fail-fast: false
-      max-parallel: 2
+      max-parallel: 1
       matrix:
         asterisk_version: [ master, 23, 22, 21 ]
         base_version: [ 9-minimal ]