If SERIES=antelope, release.sh would run the `=Antelope` command:
/home/zuul/scripts/release-tools/release.sh: line 102: =Antelope: command not found
This was not fatal because `set +e` was set earlier, but caused the
content argument of launchpad_add_comment_set_status.py to be incorrect.
Change-Id: Iebfb022be57ea5a59c42cedd58af9582be189ab0
007413ca92