Fix default export usage in my definition for react-global-configuration (#28775)

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Select one of these and delete the others:

If adding a new definition:
- [ ] The package does not already provide its own types, or cannot have its `.d.ts` files generated via `--declaration`
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types/react-global-configuration/index.d.ts

@@ -9,11 +9,7 @@ export interface Options {
     assign: boolean;
 }
 
-declare namespace ReactGlobalConfiguration {
-    function set(newConfiguration: any, newOptions?: Options): void;
-    function get(key?: string): any;
-    function get<Value = any>(key: string, fallbackValue: Value): Value;
-    function serialize(): string;
-}
-
-export default ReactGlobalConfiguration;
+export function set(newConfiguration: any, newOptions?: Options): void;
+export function get(key?: string): any;
+export function get<Value = any>(key: string, fallbackValue: Value): Value;
+export function serialize(): string;

types/react-global-configuration/tsconfig.json

@@ -14,7 +14,8 @@
         ],
         "types": [],
         "noEmit": true,
-        "forceConsistentCasingInFileNames": true
+        "forceConsistentCasingInFileNames": true,
+        "allowSyntheticDefaultImports": true
     },
     "files": [
         "index.d.ts",