tests/test-hooklib-reject_merge_commits.t

tests: fix glob pattern for dynamic timer alignment

The number of space characters varies depending on the number of digits of the
timer, making some tests fail on slow machines in an unintended way:

```diff
--- /build/mercurial-6.1/tests/test-merge-halt.t
+++ /build/mercurial-6.1/tests/test-merge-halt.t.err
@@ -210,6 +210,6 @@
   merge halted after failed merge (see hg resolve)
   [240]
   $ hg shelve --list
-  default         (* ago)    changes to: foo (glob)
+  default         (11s ago)   changes to: foo
   $ hg unshelve --abort
   unshelve of 'default' aborted
ERROR: test-merge-halt.t output changed
```

Differential Revision: https://phab.mercurial-scm.org/D12381

  $ cat <<EOF >> $HGRCPATH
  > [extensions]
  > hooklib =
  > 
  > [phases]
  > publish = False
  > EOF
  $ hg init a
  $ hg --cwd a debugbuilddag '.:parent.:childa*parent/childa<parent@otherbranch./childa'
  $ hg --cwd a log -G
  o    changeset:   4:a9fb040caedd
  |\   branch:      otherbranch
  | |  tag:         tip
  | |  parent:      3:af739dfc49b4
  | |  parent:      1:66f7d451a68b
  | |  user:        debugbuilddag
  | |  date:        Thu Jan 01 00:00:04 1970 +0000
  | |  summary:     r4
  | |
  | o  changeset:   3:af739dfc49b4
  | |  branch:      otherbranch
  | |  parent:      0:1ea73414a91b
  | |  user:        debugbuilddag
  | |  date:        Thu Jan 01 00:00:03 1970 +0000
  | |  summary:     r3
  | |
  +---o  changeset:   2:a6b287721c3b
  | |/   parent:      0:1ea73414a91b
  | |    parent:      1:66f7d451a68b
  | |    user:        debugbuilddag
  | |    date:        Thu Jan 01 00:00:02 1970 +0000
  | |    summary:     r2
  | |
  o |  changeset:   1:66f7d451a68b
  |/   tag:         childa
  |    user:        debugbuilddag
  |    date:        Thu Jan 01 00:00:01 1970 +0000
  |    summary:     r1
  |
  o  changeset:   0:1ea73414a91b
     tag:         parent
     user:        debugbuilddag
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     r0
  
  $ hg init b
  $ cat <<EOF >> b/.hg/hgrc
  > [hooks]
  > pretxnchangegroup.reject_merge_commits = \
  >   python:hgext.hooklib.reject_merge_commits.hook
  > EOF
  $ hg --cwd b pull ../a -r a6b287721c3b
  pulling from ../a
  adding changesets
  adding manifests
  adding file changes
  error: pretxnchangegroup.reject_merge_commits hook failed: a6b287721c3b rejected as merge on the same branch. Please consider rebase.
  transaction abort!
  rollback completed
  abort: a6b287721c3b rejected as merge on the same branch. Please consider rebase.
  [255]
  $ hg --cwd b pull ../a -r 1ea73414a91b
  pulling from ../a
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files
  new changesets 1ea73414a91b (1 drafts)
  (run 'hg update' to get a working copy)
  $ hg --cwd b pull ../a -r a9fb040caedd
  pulling from ../a
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 0 changes to 0 files
  new changesets 66f7d451a68b:a9fb040caedd (3 drafts)
  (run 'hg update' to get a working copy)