Update pygmt/tests/test_legend.py [skip ci]

Author: seisman

pygmt/tests/test_legend.py

@@ -103,7 +103,7 @@ def test_legend_stringio(legend_spec):
     spec = io.StringIO(legend_spec)
     fig = Figure()
     fig.basemap(projection="x6i", region=[0, 1, 0, 1], frame=True)
-    fig.legend(spec, position=Position("MC", cstype="outside", anchor="CM"), width="5i")
+    fig.legend(spec, position=Position("MC", cstype="outside", anchor="MC"), width="5i")
     return fig