Update ubuntu in CI (#29)

* Update to Ubuntu 22.04 in CI workflows

See (actions/runner-images#11101) for details.

* Ignore local build dir

Author: edan-bainglass

.github/workflows/deploy.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   deploy:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - name: Checkout
         uses: actions/checkout@v3

.gitignore

@@ -2,3 +2,7 @@ _site/
 .sass-cache/
 .jekyll-metadata/
 .jekyll-cache/
+
+# Build files
+.bundle/
+vendor/bundle/