Update documentation links

[viktorix]

There are some links in docblocks that have been updated in ClassicPress core. We should migrate those links to ensure we're linking to our documentation.

• [ ] https://github.com/ClassicPress/ClassicPress/blob/181e49be1359cfcd18c8b1b104de6d29a08dc2c0/src/wp-admin/network/index.php#L56
• [ ] https://github.com/ClassicPress/ClassicPress/blob/a5170fb3596e7ad57f4e9f2edfc14c84659583ec/src/wp-admin/network/user-new.php#L30
• [ ] https://github.com/ClassicPress/ClassicPress/blob/94b1ccab240e5a86a9184b3059782a036bb51fef/src/wp-admin/import.php#L77
• [ ] https://github.com/ClassicPress/ClassicPress/blob/a5170fb3596e7ad57f4e9f2edfc14c84659583ec/src/wp-admin/network/users.php#L214
• [ ] https://github.com/ClassicPress/ClassicPress/blob/a5170fb3596e7ad57f4e9f2edfc14c84659583ec/src/wp-admin/network/site-new.php#L33
• [ ] https://github.com/ClassicPress/ClassicPress/blob/a5170fb3596e7ad57f4e9f2edfc14c84659583ec/src/wp-admin/network/sites.php#L46
• [ ] https://github.com/ClassicPress/ClassicPress/blob/6ec372d777a1d0be84acb35f9e603760db2fec7b/src/wp-includes/admin-bar.php#L168
• [ ] https://github.com/ClassicPress/ClassicPress/blob/6ec372d777a1d0be84acb35f9e603760db2fec7b/src/wp-includes/admin-bar.php#L178
• [ ] https://github.com/ClassicPress/ClassicPress/blob/e3456bafe12836f2314a9b983906c2ce5f3ea221/src/wp-admin/about.php#L103
• [ ] https://github.com/ClassicPress/ClassicPress/blob/e3456bafe12836f2314a9b983906c2ce5f3ea221/src/wp-admin/about.php#L104
• [ ] https://github.com/ClassicPress/ClassicPress/blob/a5170fb3596e7ad57f4e9f2edfc14c84659583ec/src/wp-admin/setup-config.php#L181
• [ ] https://github.com/ClassicPress/ClassicPress/blob/35fd06cfd50c34f3fa5ff8092cdff06e19177bbd/src/wp-admin/includes/class-wp-automatic-updater.php#L896
• [ ] https://github.com/ClassicPress/ClassicPress/blob/a5170fb3596e7ad57f4e9f2edfc14c84659583ec/src/wp-admin/includes/ms.php#L1260
• [ ] https://github.com/ClassicPress/ClassicPress/blob/a5170fb3596e7ad57f4e9f2edfc14c84659583ec/src/wp-admin/update-core.php#L222