Fix QTEMP on M95, fixes #377

Signed-off-by: Sara Damiano <sdamiano@stroudcenter.org>

src/TinyGsmClientM95.h

@@ -387,7 +387,7 @@ class TinyGsmM95 : public TinyGsmModem<TinyGsmM95>,
    */
  protected:
   float getTemperatureImpl() {
-    sendAT(GF("+QTEMP"));
+    sendAT(GF("+QTEMP?"));
     if (waitResponse(GF(GSM_NL "+QTEMP:")) != 1) {
       return static_cast<float>(-9999);
     }