fix: update misleading Docker Hub references to GitHub Container Registry in workflow

Co-authored-by: superbarne <1502820+superbarne@users.noreply.github.com>

Author: Copilot

.github/workflows/docker.yml

@@ -26,7 +26,7 @@ permissions:
 
 jobs:
   push_to_registry:
-    name: Push Docker image to Docker Hub
+    name: Push Docker image to GitHub Container Registry
 
     runs-on: ${{ matrix.config.runs_on }}
     env:
@@ -62,7 +62,7 @@ jobs:
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
 
-      - name: Log in to Docker Hub
+      - name: Log in to GitHub Container Registry
         uses: docker/login-action@v3
         with:
           registry: ghcr.io