docs: Add 4.2 SQL schema links
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Connect to MySQL as a user with sufficient privileges and issue the
-following commands below if you are running the 4.2 or master version of PowerDNS:
+following commands below if you are running the 4.3 or master version of PowerDNS:
- Please find `the 4.1 schema on GitHub <https://github.com/PowerDNS/pdns/blob/rel/auth-4.1.x/modules/gmysqlbackend/schema.mysql.sql>`_.
+ Please find `the 4.2 schema <https://github.com/PowerDNS/pdns/blob/rel/auth-4.2.x/modules/gmysqlbackend/schema.mysql.sql>`_ and `the 4.1 schema <https://github.com/PowerDNS/pdns/blob/rel/auth-4.1.x/modules/gmysqlbackend/schema.mysql.sql>`_ on GitHub.
.. literalinclude:: ../../modules/gmysqlbackend/schema.mysql.sql