git: update to v2.29.0

Update to git version v2.29.0, this requires changes for these
upstream commits:

* dbbcd44fb47347a3fdbee88ea21805b7f4ac0b98
  strvec: rename files from argv-array to strvec

* 873cd28a8b17ff21908c78c7929a7615f8c94992
  argv-array: rename to strvec

* d70a9eb611a9d242c1d26847d223b8677609305b
  strvec: rename struct fields

* 6a67c759489e1025665adf78326e9e0d0981bab5
  test-lib-functions: restrict test_must_fail usage

Signed-off-by: Christian Hesse <mail@eworm.de>
7 files changed