VMware: update test name

A test to check login to the VC or ESX was called test_VC_Connection.
The name has been changed to a more appropriate one reflecting what
is actually tested: test_login_retries.

This test is run on the VC and the ESX drivers.

Change-Id: Ic156003a29e0863b5aae593127dd78edd78f0912
Merge "VMware: update test name"