runner/job_list: use case-insensitive regular expressions

There are some KMS tests that are case-sensitive. Eventually,
those could be blocklisted with a different case, causing troubles
for CI runs.

As it makes no sense to have the same test name with different
cases, handle regular expressions in a case-insensitive way.

Reviewed-by: Kamil Konieczny <kamil.konieczny@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>