chore: add gzip-size action (#767)

.github/workflows/gzip.yml

@@ -0,0 +1,19 @@
+name: Compressed Size
+
+on: [pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-node@v3
+        with:
+          node-version: 18
+          cache: npm
+      - uses: preactjs/compressed-size-action@v2
+        with:
+          clean-script: clean
+          pattern: ./**/*.js
+          exclude: ./{scripts/**/*,docs/**/*,_site/**/*,node_modules/**/*,*.config.js}