Disable ContentCapture debug logging by default

ContentCapture allows dynamic changing of logging behavior. The
current default sets a relatively high amount of debug logging on
debuggable (userdebug/eng) builds, which should be avoided.

Disable the debug log by default; devs can still enable more verbose
logging as needed on such builds.

Bug: 436095548
Test: presubmit
Flag: EXEMPT trivial logging change
Change-Id: I729835072ce31cc4b2b98d519aa911c2ff8b2046