Wording of Mysql support.

doc/install/requirements.md

@@ -94,11 +94,11 @@ installation (e.g. the number of users, projects, etc).
 We currently support the following databases:
-- PostgreSQL
-- MySQL/MariaDB
+- PostgreSQL (highly recommended)
+- MySQL/MariaDB (doesn't support all features)
 We **highly recommend** the use of PostgreSQL instead of MySQL/MariaDB as not all
-features of GitLab may work with MySQL/MariaDB:
+features of GitLab work with MySQL/MariaDB:
 1. MySQL support for subgroups was [dropped with GitLab 9.3][post].
    See [issue #30472][30472] for more information.