fix: add Docker Hub login step to build workflow

.gitea/workflows/build.yml

@@ -6,8 +6,16 @@ on:
       - main
 
 jobs:
+  dockerhub-login:
+    name: Log In To Docker Hub
+    runs-on: ubuntu-latest
+    steps:
+      - name: Log in to Docker Hub
+        run: echo "${{ secrets.DOCKERHUB_TOKEN }}" | docker login docker.io -u "${{ secrets.DOCKERHUB_USERNAME }}" --password-stdin
+
   build:
     name: Build And Publish Production Image
+    needs: dockerhub-login
     runs-on: ubuntu-latest
     env:
       REGISTRY: gitea.lab