use GITHUB_TOKEN instead of PAT for ghcr.io publishing

Author: rpardini

.github/workflows/master-latest.yaml

@@ -36,8 +36,8 @@ jobs:
         uses: docker/login-action@v1
         with:
           registry: ghcr.io
-          username: ${{ secrets.DOCKER_GITHUB_USERNAME }}
-          password: ${{ secrets.DOCKER_GITHUB_PAT }}
+          username: ${{ github.repository_owner }} # github username or org
+          password: ${{ secrets.GITHUB_TOKEN }}    # github actions builtin token. repo has to have pkg access.
 
       # the arm64 is of course much slower due to qemu, so build and push amd64 **first**
       # due to the way manifests work, the gap between this and the complete push below

.github/workflows/tags.yaml

@@ -49,8 +49,8 @@ jobs:
         uses: docker/login-action@v1
         with:
           registry: ghcr.io
-          username: ${{ secrets.DOCKER_GITHUB_USERNAME }}
-          password: ${{ secrets.DOCKER_GITHUB_PAT }}
+          username: ${{ github.repository_owner }} # github username or org
+          password: ${{ secrets.GITHUB_TOKEN }}    # github actions builtin token. repo has to have pkg access.
 
       # the arm64 is of course much slower due to qemu, so build and push amd64 **first**
       # due to the way manifests work, the gap between this and the complete push below