tests/test-check-code.t

test: rename 'test-push-r.t' to 'test-push.t'

We do not have a simple test for 'hg push' but we have multiple tiny tests for
various aspect of it. We'll unify them into a single file, and we start with
'test-push-r.t'. The code is unchanged but we renamed the repository used to
avoid collision with other tests we'll import in coming changesets.

Test timing for the record:

start   end     cuser   csys    real      Test
  1.850   2.640   0.650   0.090   0.790   test-push-validation.t
  2.640   3.520   0.760   0.090   0.880   test-push-hook-lock.t
  0.000   1.850   1.560   0.210   1.850   test-push-r.t

#require test-repo

  $ . "$TESTDIR/helpers-testrepo.sh"
  $ check_code="$TESTDIR"/../contrib/check-code.py
  $ cd "$TESTDIR"/..

New errors are not allowed. Warnings are strongly discouraged.
(The writing "no-che?k-code" is for not skipping this file when checking.)

  $ hg locate | sed 's-\\-/-g' |
  >   xargs "$check_code" --warnings --per-file=0 || false
  Skipping hgext/fsmonitor/pywatchman/__init__.py it has no-che?k-code (glob)
  Skipping hgext/fsmonitor/pywatchman/bser.c it has no-che?k-code (glob)
  Skipping hgext/fsmonitor/pywatchman/capabilities.py it has no-che?k-code (glob)
  Skipping hgext/fsmonitor/pywatchman/msc_stdint.h it has no-che?k-code (glob)
  Skipping hgext/fsmonitor/pywatchman/pybser.py it has no-che?k-code (glob)
  Skipping i18n/polib.py it has no-che?k-code (glob)
  Skipping mercurial/httpclient/__init__.py it has no-che?k-code (glob)
  Skipping mercurial/httpclient/_readers.py it has no-che?k-code (glob)
  Skipping mercurial/statprof.py it has no-che?k-code (glob)