VOL-5115 - Create release branch voltha-2.12-beta

VERISON
-------
  o Bump minor version to avoid conflicts with beta release branch version.

Change-Id: Ic1bdb8fa70d070282056dc086c1b60a733960342
diff --git a/VERSION b/VERSION
index e91f104..bd8293a 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-7.4.5
+7.4.6