Make ALWAYS_ENABLED_REGISTRY_TYPE read-only

Author: mbg

src/start-proxy.ts

@@ -192,7 +192,7 @@ function isPAT(value: string) {
  * enabled, because generic CodeQL workflow components may use them rather than just
  * language-specific components.
  */
-export const ALWAYS_ENABLED_REGISTRY_TYPE = ["git_source"];
+export const ALWAYS_ENABLED_REGISTRY_TYPE = ["git_source"] as const;
 
 type RegistryMapping = Partial<Record<BuiltInLanguage, string[]>>;