Revert to using PAT for writing images

The maximum permissions of GITHUB_TOKEN secret for pull requests from public forked repositories are read according to the [docs](https://docs.github.com/en/actions/security-guides/automatic-token-authentication#permissions-for-the-github_token).

Author: mering

.github/workflows/test.yml

@@ -24,8 +24,8 @@ jobs:
         uses: docker/login-action@v2
         with:
           registry: ghcr.io
-          username: ${{ github.repository_owner }}
-          password: ${{ secrets.GITHUB_TOKEN }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.PAT_TOKEN }}
       - name: lower case repository_owner
         id: lower_case_repository_owner
         uses: ASzc/change-string-case-action@v2
@@ -57,8 +57,8 @@ jobs:
         uses: docker/login-action@v2
         with:
           registry: ghcr.io
-          username: ${{ github.repository_owner }}
-          password: ${{ secrets.GITHUB_TOKEN }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.PAT_TOKEN }}
       - name: lower case repository_owner
         id: lower_case_repository_owner
         uses: ASzc/change-string-case-action@v2