feat: updating release action to use GITHUB_TOKEN

Updating the release action to use the repos GITHUB_TOKEN instead of a
PAT as recommend: https://docs.github.com/en/packages/managing-github-packages-using-github-actions-workflows/publishing-and-installing-a-package-with-github-actions

Signed-off-by: Richard Case <richard@weave.works>

Author: richardcase

.github/workflows/release.yml

@@ -7,6 +7,7 @@ on:
 
 env:
   TAG: ${{ github.ref_name }}
+  REGISTRY: ghcr.io
 
 jobs:
   build:
@@ -19,9 +20,9 @@ jobs:
     - name: Docker login
       uses: docker/login-action@v1
       with:
-        registry: ghcr.io
-        username: ${{ secrets.DOCKER_USERNAME }}
-        password: ${{ secrets.DOCKER_PASSWORD }}
+        registry: ${{ env.REGISTRY }}
+        username: ${{ github.actor }}
+        password: ${{ secrets.GITHUB_TOKEN }}
     - name: Build docker image
       run: make docker-build TAG=${{ env.TAG }}
     - name: Push docker image