fix(ci): login to docker hub in pr

Author: bigbrozer

.github/workflows/pr.yaml

@@ -5,6 +5,10 @@ on:
     branches:
       - "master"
 
+env:
+  IMAGE_NAME: "nventiveux/syncthing"
+  DOCKER_BUILDKIT: "1"
+
 jobs:
   lint:
     name: "Linting"
@@ -34,6 +38,12 @@ jobs:
         with:
           install: true
 
+      - name: "Login to DockerHub"
+        uses: "docker/login-action@v2"
+        with:
+          username: "${{ secrets.DOCKER_USERNAME }}"
+          password: "${{ secrets.DOCKER_PASSWORD }}"
+
       - name: "Build images"
         uses: "docker/build-push-action@v3"
         with:
@@ -42,4 +52,4 @@ jobs:
           file: "./Dockerfile"
           platforms: "linux/amd64,linux/arm64,linux/arm/v7,linux/arm/v6"
           push: true
-          tags: "pr-${{ github.event.number }}"
+          tags: "${{ env.IMAGE_NAME }}:pr-${{ github.event.number }}"