Remove incorrect statement from Log docs.

The javadoc for Log stated that verbose logs are not compiled into apps
and debug logs are stripped at runtime, but this doesn't happen
automatically and is up to the app's Proguard/R8 configuration and/or
explicit use of isLoggable. Just remove this.

Fixes: 27286343
Test: m offline-sdk-docs
Change-Id: I0376b20e5c324f422a5fff0201f144e447d8eac2