Correct y limits in ProfileViewerState when min same as max

glue/viewers/profile/state.py

@@ -230,6 +230,13 @@
                 if y_max > y_min:
                     self.y_min = y_min
                     self.y_max = y_max
+                elif np.allclose(y_min, y_max):
+                    if np.allclose(y_min, 0):
+                        self.y_min = -0.1
+                        self.y_max = 0.1
+                    else:
+                        self.y_min = y_min * 0.9
+                        self.y_max = y_max * 1.1
                 else:
                     self.y_min = 0
                     self.y_max = 1