[nrf noup] test-spec: update CI-ble-test

nrf-squash! [nrf noup] ci: add .github/test-spec.yml

More granular at soc.
test-ble is not validating nrf51 and nrf91,
so it does not make sense to trigger ci on these changes.

Signed-off-by: Piotr Kosycarz <[email protected]>

Author: nordic-piks

.github/test-spec.yml

@@ -108,6 +108,8 @@
       - "boards/nordic/nrf5*"
   - any:
       - "soc/nordic/**/*"
+      - "!soc/nordic/nrf51*"
+      - "!soc/nordic/nrf9*"
   - any:
       - "subsys/pm/**/*"