Fix doc build from tarball using eventlet>0.19.0
When subprocess is monkey-patched using eventlet, trying to catch
subprocess.CalledProcessError exception won't work [1]. This breaks
doc build from a tarball, so let's catch all exceptions.
[1] https://github.com/eventlet/eventlet/issues/357
Change-Id: Ibcf535c6e4994a67fc3ec71631a81ecb91dd2845
Closes-Bug: #1693148
Javier Pena
6 years ago