update docstring

Author: LiamConnors

plotly/subplots.py

@@ -218,7 +218,7 @@ def make_subplots(
     >>> fig.add_scatter(y=[1, 3, 2], row=2, col=1) # doctest: +ELLIPSIS
     Figure(...)
 
-    or see Figure.append_trace
+    or see Figure.add_trace
 
     Example 2:
 

plotly/tools.py

@@ -249,7 +249,7 @@ def make_subplots(
     fig['data'] += [Scatter(x=[1,2,3], y=[2,1,2])]
     fig['data'] += [Scatter(x=[1,2,3], y=[2,1,2], xaxis='x2', yaxis='y2')]
 
-    # or see Figure.append_trace
+    # or see Figure.add_trace
 
     Example 2:
     # subplots with shared x axes