[nrf52,gpio] add gpio levels for high voltage mode (#9858)

Co-authored-by: J. Nick Koston <nick+github@koston.org>

tests/components/nrf52/test.nrf52-adafruit.yaml

@@ -15,3 +15,6 @@ nrf52:
       inverted: true
       mode:
         output: true
+  reg0:
+    voltage: 2.1V
+    uicr_erase: true

tests/components/nrf52/test.nrf52-mcumgr.yaml

@@ -0,0 +1,4 @@
+nrf52:
+  reg0:
+    voltage: 3.3V
+    uicr_erase: true

tests/components/nrf52/test.nrf52-xiao-ble.yaml

@@ -5,3 +5,5 @@ nrf52:
       inverted: true
       mode:
         output: true
+  reg0:
+    voltage: default