Currently, runtime tests only test the osnoise period option
(-p/--period of rtla-osnoise tools, backed by
/sys/kernel/tracing/osnoise/period_us), using the
check_with_osnoise_options function together with a hack relying on long
period (pre-set) timing out if RTLA fails to reset it to the default
value.

Extend tracer option testing to all options used by RTLA; test both RTLA
setting the default option by pre-setting the tracer to a different
value and user-requested value.

The tests are done using a script that reads the tracer values inside an
--on-threshold action, like existing tests for runtime behavior already
do. check_with_osnoise_option is modified to support grep filters, so
that it can be used together with the script pattern.

Assisted-by: Claude:claude-opus-4-6
Link: https://lore.kernel.org/r/20260709091755.58265-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>