The ntp charm only supports LTS releases and cannot be deployed
to interim releases. This change removes the ntp charm from the
gate tests on non-LTS releases.
Additionally, this change removes the groovy tests are removed
from the gate since the groovy release is EOL.
Closes-Bug: #1946040
Change-Id: If64504baea7b1458dd244c765a04546513efb9a2