Removed unnecessary HSE clock rate configuration from NUCLEO_G031K8 (target does not have HSE xtal input)

Author: AGlass0fMilk

targets/targets.json

@@ -2755,11 +2755,6 @@
             "lpticker_lptim": {
                 "help": "This target supports LPTIM. Set value 1 to use LPTIM for LPTICKER, or 0 to use RTC wakeup timer",
                 "value": 1
-            },
-            "hse_value": {
-                "help": "HSE default value is 25MHz in HAL",
-                "value": "8000000",
-                "macro_name": "HSE_VALUE"
             }
         },
         "extra_labels_add": [