Update 6 baseline images due to GMT 6.1.0 changes

Author: seisman

pygmt/tests/baseline/test_basemap_polar.png

@@ -54,9 +54,6 @@ def test_basemap_power_axis():
     return fig
 
 
-@pytest.mark.xfail(
-    reason="Baseline image not updated to use earth relief grid in GMT 6.1.0",
-)
 @pytest.mark.mpl_image_compare
 def test_basemap_polar():
     "Create a polar basemap plot"

pygmt/tests/baseline/test_coast_iceland.png

@@ -25,9 +25,6 @@ def test_coast():
     return fig
 
 
-@pytest.mark.xfail(
-    reason="Baseline image not updated to use earth relief grid in GMT 6.1.0",
-)
 @pytest.mark.mpl_image_compare
 def test_coast_iceland():
     "Test passing in R as a list"

pygmt/tests/baseline/test_colorbar_positioned_using_justification_code.png

@@ -37,9 +37,6 @@ def test_colorbar_positioned_using_map_coordinates():
     return fig
 
 
-@pytest.mark.xfail(
-    reason="Baseline image not updated to use earth relief grid in GMT 6.1.0",
-)
 @pytest.mark.mpl_image_compare
 def test_colorbar_positioned_using_justification_code():
     """

pygmt/tests/baseline/test_config_font_annot.png

@@ -40,9 +40,6 @@ def test_config():
     return fig
 
 
-@pytest.mark.xfail(
-    reason="Baseline image not updated to use earth relief grid in GMT 6.1.0",
-)
 @pytest.mark.mpl_image_compare
 def test_config_font_one():
     """
@@ -57,9 +54,6 @@ def test_config_font_one():
     return fig
 
 
-@pytest.mark.xfail(
-    reason="Baseline image not updated to use earth relief grid in GMT 6.1.0",
-)
 @pytest.mark.mpl_image_compare
 def test_config_font_annot():
     """