Add explicit github actions permissions

Signed-off-by: alexey semenyuk <alexsemenyuk88@gmail.com>

Author: alex-semenyuk

.github/workflows/docker_main.yml

@@ -8,6 +8,9 @@ on:
 jobs:
   docker:
     runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
     steps:
       - uses: actions/checkout@v4
 
@@ -37,4 +40,4 @@ jobs:
       - name: Push head tag
         run: |
           echo ${{ secrets.GITHUB_TOKEN }} | docker login ghcr.io -u $GITHUB_ACTOR --password-stdin
-          docker push ghcr.io/hyperledger/firefly-ethconnect:head
+          docker push ghcr.io/hyperledger/firefly-ethconnect:head