Remove a redundant call of starting DumpstateService

A new DumpstateService instance is created and published,
when the start service is invoked. The member field 'ds_' in
DumpstateService would be null, and a crash could happen when
DumpstateService tried to access it.

Bug: 164340819
Test: atest dumpstate_test
Test: atest dumpstate_smoke_test
Test: Manual cancel report via the notification

Change-Id: Ib77f114414ed0f4f916bd74de151665d65fe4118