test: bump test-run to new version

Bump test-run to new version with the following improvements:

- Introduce flaky tests statistics [1]

[1] tarantool/test-run@7729a4c

Part of tarantool/tarantool-qa#299

NO_DOC=testing stuff
NO_TEST=testing stuff
NO_CHANGELOG=testing stuff

(cherry picked from commit f05e683c)