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>