st3m: Add a setting for auto-connecting to camp wifi

@Anon, you can use st3m.wifi.is_connected() to find out connection status.

python_payload/mypystubs/network.pyi

+from st3m.goose import Optional
+
+STA_IF: int
+
+class WLAN:
+    def __init__(self, mode: int) -> None:
+        pass
+    def active(self, active: bool) -> bool:
+        return False
+    def connect(self, ssid: bytes, key: Optional[bytes] = None) -> None:
+        pass
+    def isconnected(self) -> bool:
+        return False