Revert "Update dependencies (#6167)" (#6168)

This reverts commit 0420c548da.

.github/workflows/docker.yml

@@ -0,0 +1,18 @@
+name: Docker build
+on:
+  push:
+    branches:
+      - master
+      - develop
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v1
+    - name: Pull previous build result (for cache)
+      run: docker pull misskey/misskey:latest
+    - name: Build docker container
+      run: docker build --cache-from misskey/misskey:latest -t misskey/misskey .