Gallery examples: Minor typo fixes (#3311)

Author: yvonnefroehlich

examples/gallery/basemaps/double_y_axes.py

@@ -1,5 +1,5 @@
 """
-Double Y axes graph
+Double Y-axes graph
 ===================
 
 The ``frame`` parameter of the plotting methods of the :class:`pygmt.Figure`

examples/gallery/basemaps/ternary.py

@@ -42,5 +42,5 @@
 
 # Add a colorbar indicating the values given in the fourth column of
 # the input dataset
-fig.colorbar(position="JBC+o0c/1.5c", frame=["x+lPermittivity"])
+fig.colorbar(position="JBC+o0c/1.5c", frame="x+lPermittivity")
 fig.show()

examples/gallery/embellishments/inset.py

@@ -18,7 +18,7 @@
 fig.coast(region="MG+r2", land="brown", water="lightblue", shorelines="thin", frame="a")
 # Create an inset, setting the position to top left, the width to 3.5 cm, and
 # the x- and y-offsets to 0.2 cm. The margin is set to 0, and the border is
-# "gold" with a pen size of 1.5p.
+# "gold" with a pen size of 1.5 points.
 with fig.inset(position="jTL+w3.5c+o0.2c", margin=0, box="+p1.5p,gold"):
     # Create a figure in the inset using coast. This example uses the azimuthal
     # orthogonal projection centered at 47E, 20S. The land color is set to