Don't install Ruby or Python dependencies unnecessarily (#7084)

* Don't install Ruby or Python dependencies unnecessarily

* Less repeated code

* Cleaner code

packages/ruby/install-ruby.ts

@@ -61,6 +61,14 @@ function getRubyPath(meta: Meta, gemfileContents: string) {
 // process.env.GEM_HOME), and returns
 // the absolute path to it
 export async function installBundler(meta: Meta, gemfileContents: string) {
+  // If the new File System API is used (`avoidTopLevelInstall`), the Install Command
+  // will have already installed the dependencies, so we don't need to do it again.
+  if (meta.avoidTopLevelInstall) {
+    debug(
+      `Skipping bundler installation, already installed by Install Command`
+    );
+  }
+
   const { gemHome, rubyPath, gemPath, vendorPath, runtime } = getRubyPath(
     meta,
     gemfileContents