sql: enable locality validation when setting zone configs for secondary tenants

[arulajmani]

Is your feature request related to a problem? Please describe.

Now that #67098 has landed, tenants can get access to node locality information via the connecter API. This means the check that skips locality validation when setting zone configs for secondary tenants can be removed once we move the prototype to master.

[irfansharif]

I think this was just #69275.