perf: use the `perf--` prefix for perf command
This is the one command namespace where they should not be any ambiguity about
command that should be in it. The perf extensions is only adding performance
related command.
so this is a good ground to start putting dash folding to the tests.
Differential Revision: https://phab.mercurial-scm.org/D9516
#require docutils gettext
Error: the current ro localization has some rst defects exposed by
moving pager to core. These two warnings about references are expected
until the localization is corrected.
$ $TESTDIR/check-gendoc ro
checking for parse errors
gendoc.txt:58: (WARNING/2) Inline interpreted text or phrase reference start-string without end-string.
gendoc.txt:58: (WARNING/2) Inline interpreted text or phrase reference start-string without end-string.