ci(github): fix creds

ref: #2 #1 templates/mkdocs#1

Author: jon-nfc

.github/workflows/docker.yaml

@@ -22,8 +22,8 @@ env:
   DOCKER_BUILD_IMAGE_TAG: ${{ github.sha }}
   DOCKER_PUBLISH_REGISTRY: "docker.io"
   DOCKER_PUBLISH_IMAGE_NAME: "nofusscomputing/mkdocs-ci"
-  DOCKER_BUILD_USERNAME: admin
-  DOCKER_BUILD_PASSWORD: Harbor12345
+  DOCKER_BUILD_USERNAME: ${{ github.actor }}
+  DOCKER_BUILD_PASSWORD: ${{ secrets.GITHUB_TOKEN }}
   DOCKER_PUBLISH_USERNAME: ${{ secrets.NFC_DOCKERHUB_USERNAME }}
   DOCKER_PUBLISH_PASSWORD: ${{ secrets.NFC_DOCKERHUB_TOKEN }}