ci: re-trigger PR validation

GitHub dropped the pull_request synchronize dispatch for ea46648: the
commit's github-actions check-suite closed as complete carrying only the
DCO check, so the PR workflow never ran and its required ci-ok context
was never created. Close/reopen did not re-dispatch it and check-suite
rerequest is not permitted for that suite, so an empty commit is the
remaining way to produce the events. No code change.

Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>

Author: DeusData