fix(frontend): stick with ESLint v9 for now (#653)

The surrounding ecosystem is still updating to support v10, so for now
we need to stick with v9

Author: G-Rath

variants/frontend-base/js-lint/template.rb

@@ -4,8 +4,8 @@
 add_js_dependencies %w[
   @eslint-community/eslint-plugin-eslint-comments
   @stylistic/eslint-plugin-js@3
-  @eslint/js
-  eslint
+  @eslint/js@9
+  eslint@9
   eslint-config-ackama
   eslint-plugin-n
   eslint-plugin-import