phases: make `allphases` a list on py3 also
Pytype complained that `range` doesn't support slicing, so make this a list like
it was on py2.
Differential Revision: https://phab.mercurial-scm.org/D7468
#require test-repo jshint hg10
$ . "$TESTDIR/helpers-testrepo.sh"
run jshint on all tracked files ending in .js except vendored dependencies
$ cd "`dirname "$TESTDIR"`"
$ testrepohg locate 'set:**.js' \
> 2>/dev/null \
> | xargs jshint