Don't waste time installing packages that are already present

GitHub updated their `ubuntu-latest` and it now has all the packaages
we want except for `gyp`. So in most cases we can get away with installing
nothing.

Saves 8-10 seconds per builds.

Author: byroot

railties/lib/rails/generators/app_base.rb

@@ -618,11 +618,16 @@ def dockerfile_build_packages
       end
 
       def ci_packages
-        if depends_on_system_test?
-          dockerfile_build_packages << "google-chrome-stable"
-        else
-          dockerfile_build_packages
-        end
+        dockerfile_build_packages - [
+          # GitHub Actions doesn't have build-essential,
+          # but it's a meta-packages and all its dependencies are already installed.
+          "build-essential",
+          "git",
+          "pkg-config",
+          "libyaml-dev",
+          "unzip",
+          "python-is-python3",
+        ]
       end
 
       def css_gemfile_entry

railties/lib/rails/generators/rails/app/templates/github/ci.yml.tt

@@ -102,9 +102,11 @@ jobs:
 
     <%- end -%>
     steps:
+      <%- unless ci_packages.empty? -%>
       - name: Install packages
         run: sudo apt-get update && sudo apt-get install --no-install-recommends -y <%= ci_packages.join(" ") %>
 
+      <%- end -%>
       - name: Checkout code
         uses: actions/checkout@v4
 

railties/lib/rails/generators/rails/plugin/templates/github/ci.yml.tt

@@ -63,9 +63,6 @@ jobs:
 
     <%- end -%>
     steps:
-      - name: Install packages
-        run: sudo apt-get update && sudo apt-get install --no-install-recommends -y <%= ci_packages.join(" ") %>
-
       - name: Checkout code
         uses: actions/checkout@v4