Update README

.github/workflows/build_image.yml

@@ -6,7 +6,7 @@ on:
 jobs:
   build:
     runs-on: ubuntu-20.04
-    name: Clone telegram api server repo
+    name: Build amd64 and arm64 images
     steps:
       - name: Checkout API repo
         uses: actions/checkout@v2
@@ -30,7 +30,15 @@ jobs:
         uses: docker/setup-qemu-action@v1
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v1
-      - name: Build Docker image
+      - name: Login to GHCR
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GCHR_PAT }}
+      - name: Prepare for push
+        id: prep
         run: |
           DOCKER_IMAGE=ghcr.io/${{ github.repository_owner }}/tdlib-telegram-bot-api-docker/telegram-api-server
           VERSION=edge