Bluetooth: CI: trigger bsim on testlib change

Some bsim tests have a dependency on testlib. Since testlib does not
have a stable API, it's a good idea to run the bsim tests.

Signed-off-by: Aleksander Wasaznik <aleksander.wasaznik@nordicsemi.no>

.github/workflows/bsim-tests.yaml

@@ -8,6 +8,7 @@ on:
       - "west.yml"
       - "subsys/bluetooth/**"
       - "tests/bsim/**"
+      - "tests/bluetooth/common/testlib/**"
       - "samples/bluetooth/**"
       - "boards/posix/**"
       - "soc/posix/**"