tests: zephyr: drivers: flash: common: Remove the non-existent test

Removes flash.common test for nRF7120.

Signed-off-by: Erdem Simsek <erdem.simsek@nordicsemi.no>

Author: erdemsimsek

tests/zephyr/drivers/flash/common/testcase.yaml

@@ -31,8 +31,3 @@ tests:
       - nrf54l15dk/nrf54l15/cpuapp
     extra_args:
       - DTC_OVERLAY_FILE="boards/nrf54l15dk_nrf54l15_cpuapp_sqspi.overlay"
-  nrf.extended.drivers.flash.common.mramc:
-    platform_allow:
-      - nrf7120dk/nrf7120/cpuapp
-    integration_platforms:
-      - nrf7120dk/nrf7120/cpuapp