Add filter to pages, cache linguist install

.github/workflows/pages.yml

@@ -2,13 +2,19 @@ name: Pages
 
 on:
   push:
+    paths:
+      - 'docs/**'
+      - 'javascript/**'
+      - 'python/**'
+      - 'README.rst'
+      - '**/*.rst'
   workflow_dispatch:
   schedule:
   - cron: "0 0 * * 1"
 
 jobs:
   build:
-    runs-on: 'ubuntu-22.04'
+    runs-on: 'ubuntu-latest'
 
     steps:
     - uses: actions/checkout@v3
@@ -30,8 +36,11 @@ jobs:
       with:
         node-version: 22
 
-    - name: Install Linguist
-      run: sudo gem install github-linguist
+    - name: Install git, linguist
+      uses: awalsh128/cache-apt-pkgs-action@latest
+      with:
+        packages: git ruby-github-linguist
+        version: docs
 
     - name: Build sphinx docs
       run: make docs_dependencies html
@@ -42,7 +51,7 @@ jobs:
 
   deploy:
     needs: build
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
 
     permissions:
       pages: write     # to deploy to Pages