Add missing copyright headers to Metro Flow libdefs (#58722)

Summary:
X-link: react/metro#1991

Pull Request resolved: #58722

Add Metro's standard open-source MIT copyright header to three Flow library definitions flagged by the copyright-header check. Replace the internal-only header in strip-ansi with the open-source variant, and keep overlapping React Native Flow definitions synchronized.

## Changelog:
[Internal] -

Reviewed By: cortinico

Differential Revision: D122172879

fbshipit-source-id: a7cf4cef35c41f81cae3ecbfb30c913501d03039

Author: cipolleschi

flow-typed/npm/react-test-renderer_v16.x.x.js

@@ -1,3 +1,10 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
 // Type definitions for react-test-renderer 16.x.x
 // Ported from: https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/react-test-renderer
 

flow-typed/npm/yargs_v17.x.x.js

@@ -1,3 +1,10 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
 // flow-typed version: f7c859e705/yargs_v17.x.x/flow_>=v0.104.x
 
 declare module 'yargs' {