[RFC PATCH 0/5] fix issues in transfer.credentialsInUrl

This is on top of [1], and given the "rc" phase is an RFC. This:

 * Fixes the issue of the transfer.credentialsInUrl (now renamed) not
   finding passwords in "pushurl" URLs (in my case, the only place
   where I'd actually put a password in a URL in a config...)

 * 1/5 fixes a bug in an existing test, but I didn't think it was
   worth bothering with for 2.37.0.

 * Adds missing test coverage for reading the config from a file, not
   the CLI.

 * 3/5 is a WIP CI target to spot the type of issue I fixed in [2],
   it's not the first time where we have a NO_CURL=Y breakage land on
   master...

 * 4/5 attemps to "really" fix the duplicate warnings we emit, I think
   the approach there is good, especially the part where we shouldn't
   emit it twice in-process.

   But this currently misses e.g. "git ls-remote". I wonder if we
   should just stick that git_config_push_parameter() condition into
   packet_trace_identity() and call it a day.

 * 5/5 fixes the (major) blind spot of the warning missing "pushurl" config.

I think this is all non-RFC quality, except the "ls-remote" case, and us missing tests for that & other transport users that aren't clone/fetch/push.

Derrick: Are you interested in picking this up & pursuing it after the
release, with whatever fix-ups/rewrites etc. that you find
appropriate?

1. https://lore.kernel.org/git/cover-0.2-00000000000-20220615T103852Z-avarab@gmail.com/
2. https://lore.kernel.org/git/cover-0.1-00000000000-20220615T103609Z-avarab@gmail.com/

Ævar Arnfjörð Bjarmason (5):
  push tests: add a missing "test_line_count"
  fetch+push tests: add missing coverage for 6dcbdc0d661
  CI: add a linux-BUILD-vars job
  fetch: stop emitting duplicate transfer.credentialsInUrl=warn warnings
  transport: check remote.<name>pushurl with transfer.credentialsInUrl

 .github/workflows/main.yml |  3 ++
 builtin/clone.c            |  5 ++-
 builtin/fetch.c            |  4 ++
 builtin/push.c             |  6 ++-
 ci/run-build-and-tests.sh  | 30 ++++++++++++++
 remote.c                   | 82 +++++++++++++++++++++++++++-----------
 remote.h                   | 14 +++++++
 t/t5516-fetch-push.sh      | 46 ++++++++++++++++++++-
 t/t5601-clone.sh           |  2 +-
 9 files changed, 164 insertions(+), 28 deletions(-)