fix: use OpenOCD flash method on microbit v2 when using Nordic Semi SoftDevice

Signed-off-by: deadprogram <[email protected]>

Author: deadprogram

targets/microbit-v2-s113v7.json

@@ -1,3 +1,4 @@
 {
-	"inherits": ["microbit-v2", "nrf52833-s113v7"]
+	"inherits": ["microbit-v2", "nrf52833-s113v7"],
+	"flash-method": "openocd"
 }