fix set_text and property setter

Author: FoamyGuy

adafruit_display_text/__init__.py

@@ -307,7 +307,7 @@ def text(self):
 
     @text.setter  # Cannot set color or background color with text setter, use separate setter
     def text(self, new_text):
-        self._set_text(text=new_text, scale=self.scale)
+        self._set_text(new_text, self.scale)
 
     @property
     def bounding_box(self):

adafruit_display_text/bitmap_label.py

@@ -526,3 +526,6 @@ def _set_font(self, new_font):
             self._reset_text(font=new_font, scale=self.scale)
         else:
             raise RuntimeError("font is immutable when save_text is False")
+
+    def _set_text(self, new_text, scale):
+        self._reset_text(text=new_text, scale=self.scale)