[PATCH V5 0/3] refactor t1517 to focus on help output outside a repository

This series refactors t1517-outside-repo.sh to focus on testing `git subcmd -h` outside a Git repository. It does two things:

  1. Moves the existing `update-server-info -h` test to t5200, since it
     tests behavior *inside* a repo and belongs with other update-server-info
     tests.
  
  2. Introduces a loop in t1517 that automatically verifies `-h` output
     for all main Git subcommands when run outside a repository, using
     the `nongit` helper and `git --list-cmds=main`.

This makes t1517 easier to maintain and ensures that new commands are automatically covered for this class of behavior.

Changes since v4:
  - Changes the approach from having the t1517 to test
  both help outside and inside repo to just having inside repo.
  - Drop spurious message during test 
  - Fix known breakages that actually work
  - Fix new t5200 by removing the trailing &&
  - Move the `prune -h` test to t5304

Usman Akinyemi (3):
  t/t1517: automate `git subcmd -h` tests outside a repository
  t5200: move `update-server-info -h` test from t1517
  t5304: move `prune -h` test from t1517

 t/t1517-outside-repo.sh       | 34 +++++++++++++++++++++-------------
 t/t5200-update-server-info.sh |  5 +++++
 t/t5304-prune.sh              |  5 +++++
 3 files changed, 31 insertions(+), 13 deletions(-)

Range-diff against v2:

1:  11eb3e7bfe < -:  ---------- t/t1517: automate `git subcmd -h` tests outside a repository
-:  ---------- > 1:  75a1d540e4 t/t1517: automate `git subcmd -h` tests outside a repository
2:  5cf43192d0 ! 2:  8c028256a0 t5200: move `update-server-info -h` test from t1517
    @@ t/t1517-outside-repo.sh: test_expect_success LIBCURL 'remote-http outside reposi
      
     -test_expect_success 'update-server-info does not crash with -h' '
     -	test_expect_code 129 git update-server-info -h >usage &&
    --	test_grep "[Uu]sage: git update-server-info " usage &&
    +-	test_grep "[Uu]sage: git update-server-info " usage
     -'
     -
    + test_expect_success 'prune does not crash with -h' '
    + 	test_expect_code 129 git prune -h >usage &&
    + 	test_grep "[Uu]sage: git prune " usage &&
    + 	test_expect_code 129 nongit git prune -h >usage &&
    + 	test_grep "[Uu]sage: git prune " usage
    + '
    ++
      for cmd in $(git --list-cmds=main)
      do
      	cmd=${cmd%.*} # strip .sh, .perl, etc.
    @@ t/t5200-update-server-info.sh: test_expect_success 'midx does not create duplica
      
     +test_expect_success 'update-server-info does not crash with -h' '
     +	test_expect_code 129 git update-server-info -h >usage &&
    -+	test_grep "[Uu]sage: git update-server-info " usage &&
    ++	test_grep "[Uu]sage: git update-server-info " usage
     +'
     +
      test_done
-:  ---------- > 3:  c1cdbf272f t5304: move `prune -h` test from t1517