Deprecate instance_get_all_by_filters() from conductor

This deprecates the instance_get_all_by_filters() method from
conductor, which is no longer used.

This also removes a test that was mocking the conductor method,
but that really tests nothing at all. Perhaps a new test to ensure
that the period=0 case is handled properly is in order, but this
test definitely wasn't doing that.

Related to blueprint compute-manager-objects-juno

Change-Id: I1e7bc19296d1773bbc2f5f9e77a1faf0e6ac1fe6
Deprecate instance_get_active_by_window_joined() from conductor

This deprecates the instance_get_active_by_window_joined() method
from conductor which is no longer used.

Related to blueprint compute-manager-objects-juno

Change-Id: Ia9ce0cf49180806da64cc034ad12ddf2b3f1c424