chore: update copyright years on newly added test files

Update the `Copyright (c)` year in the two newly created
`test/test.main.js` files to the current year so the `Lint Copyright
Years` CI check passes. The files were mirrored verbatim from the
existing `test/test.js` siblings (which carry their original 2022
copyright), so the copied header needs bumping for new files.

https://claude.ai/code/session_0151TCuqxNJXJZfy4XEWqKhM

Author: claude

lib/node_modules/@stdlib/regexp/reviver/test/test.main.js

@@ -1,7 +1,7 @@
 /**
 * @license Apache-2.0
 *
-* Copyright (c) 2022 The Stdlib Authors.
+* Copyright (c) 2026 The Stdlib Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.

lib/node_modules/@stdlib/regexp/to-json/test/test.main.js

@@ -1,7 +1,7 @@
 /**
 * @license Apache-2.0
 *
-* Copyright (c) 2022 The Stdlib Authors.
+* Copyright (c) 2026 The Stdlib Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.