Currently when using the built-in CA provider for Connect, root certificates are valid for 10 years, however secondary DCs get intermediates that are valid for only 1 year. There is no mechanism currently short of rotating the root in the primary that will cause the secondary DCs to renew their intermediates.
This PR adds a check that renews the cert if it is half way through its validity period.
In order to be able to test these changes, a new configuration option was added: IntermediateCertTTL which is set extremely low in the tests.
