Due to the restrictions on instance provisioning for self-hosted runners, performing
static checks (36 jobs at the time of writing) on them each time a PR is updated could
significantly burden them, consequently slowing down the entire CI system. To address
this, the decision is to trigger these checks only when an 'ok-to-test' label is added.
Meanwhile, the checks for x86_64, which are supported by GitHub-hosted runners, will
remain unchanged.
Fixes: #8998
Signed-off-by: Hyounggyu Choi <Hyounggyu.Choi@ibm.com>