Remove dimensions_in_condition from statsd metrics

The dimensions_in_condition field is not used for any configs in statsd.
The functionality that it was intended to provide will be replaced by
StateTracker which is being tracked in b/136566566.

go/remove-dic contains background information on what was
removed/changed and why

Test: bit statsd_test:*
&& atest CtsStatsdHostTestCases
&& atest GtsStatsdHostTestCases

Change-Id: Ic328fa5fe027377380ba57363d9bc77985f18376