VOL-5159 - Create a beta release branch for openolt

VERSION
-------
  o Artifically increment version string for release.
  o https://jenkins.opencord.org/job/version-tag_wildcard/466/
    Two v3.8.0 patches were processed concurrently.
    Job #1 merged but later failed VERSION file check as a duplicate
    due to pipeline tasks running concurrently.  Infrequent occurance
    but job should serialize test & merge with a semaphore guard to
    prevent this case from occuring.

Change-Id: I80d7047deb357465d04b57907251f84cf4df4df9

VERSION

@@ -1 +1 @@
-3.8.0
+3.9.0