docs: add or improve links

Author: kenjis

user_guide_src/source/database/configuration.rst

@@ -6,6 +6,9 @@ Database Configuration
     :local:
     :depth: 2
 
+.. note::
+    See :ref:`requirements-supported-databases` for currently supported database drivers.
+
 ***********
 Config File
 ***********

user_guide_src/source/tutorial/news_section.rst

@@ -14,7 +14,7 @@ Create a Database to Work with
 ******************************
 
 The CodeIgniter installation assumes that you have set up an appropriate
-database, as outlined in the :doc:`requirements </intro/requirements>`.
+database, as outlined in the :ref:`requirements <requirements-supported-databases>`.
 In this tutorial, we provide SQL code for a MySQL database, and
 we also assume that you have a suitable client for issuing database
 commands (mysql, MySQL Workbench, or phpMyAdmin).
@@ -54,7 +54,7 @@ Connect to Your Database
 The local configuration file, ``.env``, that you created when you installed
 CodeIgniter, should have the database property settings uncommented and
 set appropriately for the database you want to use. Make sure you've configured
-your database properly as described :doc:`here <../database/configuration>`::
+your database properly as described in :doc:`../database/configuration`::
 
     database.default.hostname = localhost
     database.default.database = ci4tutorial