feat(ci): update experimental workflow with proposed test flow

.woodpecker/experimental.yaml

@@ -1,8 +1,27 @@
 when:
   - event: manual
 
+services:
+  - name: database
+    image: postgres:15
+    environment:
+      - POSTGRES_PASSWORD=ci
+  - name: redis
+    image: redis:latest
+
 steps:
-  - name: test
+  - name: Tests
-    image: alpine
+    image: node:jod
     commands:
-      - ls -al
+      - apt-get update && apt-get install -y git wget curl build-essential python3 ffmpeg
+      - cp .config/ci.yml .config/default.yml
+      - cp .config/ci.yml .config/test.yml
+      - corepack enable
+      - corepack prepare pnpm@latest --activate
+      - git submodule update --init
+      - pnpm install --frozen-lockfile
+      - pnpm run build
+      - pnpm run migrate
+      - pnpm run --filter='!megalodon' test
+      - pnpm run --filter=backend --filter=misskey-js lint
+      - pnpm run --filter=frontend --filter=frontend-embed eslint