remove persistent-storage example from qpg action

Author: Wiktor Grajkowski

.github/workflows/examples-qpg.yaml

@@ -64,7 +64,6 @@ jobs:
                         --target qpg-qpg6105-lock \
                         --target qpg-qpg6105-light \
                         --target qpg-qpg6105-shell \
-                        --target qpg-qpg6105-persistent-storage \
                         --target qpg-qpg6105-light-switch \
                         --target qpg-qpg6105-thermostat \
                         build \