chore: Move older changelogs to changelogs/ (codeigniter4#9912)

Author: paulbalandan

CHANGELOG.md

@@ -562,4 +562,4 @@ This release focuses on code style. All changes (except those noted below) are c
 - Backfill non-optional parameters (https://github.com/codeigniter4/CodeIgniter4/pull/3938)
 - Change deprecated assertFileNotExists (https://github.com/codeigniter4/CodeIgniter4/pull/3862)
 
-See [CHANGELOG_4.0.md](./CHANGELOG_4.0.md)
+For the changelog of v4.0, see [CHANGELOG_4.0.md](./CHANGELOG_4.0.md).

changelogs/CHANGELOG_4.1.md

@@ -420,4 +420,4 @@
 * Small change to improve code reading by @valmorflores in https://github.com/codeigniter4/CodeIgniter4/pull/6051
 * refactor: remove `CodeIgniter\Services` by @kenjis in https://github.com/codeigniter4/CodeIgniter4/pull/6053
 
-See [CHANGELOG_4.1.md](./CHANGELOG_4.1.md)
+For the changelog of v4.1, see [CHANGELOG_4.1.md](./CHANGELOG_4.1.md).

changelogs/CHANGELOG_4.2.md

@@ -323,4 +323,4 @@
 * refactor: remove Workaround for Faker deprecation errors in PHP 8.2 by @kenjis in https://github.com/codeigniter4/CodeIgniter4/pull/6987
 * refactor: to fix psalm error by @kenjis in https://github.com/codeigniter4/CodeIgniter4/pull/6999
 
-See [CHANGELOG_4.2.md](./CHANGELOG_4.2.md)
+For the changelog of v4.2, see [CHANGELOG_4.2.md](./CHANGELOG_4.2.md).