Update version in properties file after cutting 6.11 branch (#1292)

## Goal
Update version number in trunk after 6.11 branch cut

gradle.properties

@@ -14,7 +14,7 @@ org.gradle.jvmargs=-Xmx4g -XX:+UseParallelGC -XX:MaxMetaspaceSize=1g
 # This option should only be used with decoupled projects. More details, visit
 # http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
 org.gradle.parallel=true
-version = 6.11.0-SNAPSHOT
+version = 6.12.0-SNAPSHOT
 android.useAndroidX=true
 # Enable adding baseline-prof.txt files to AAR artifacts.
 android.experimental.enableArtProfiles=true