Order parameters [skip ci]

Co-authored-by: Wei Ji <23487320+weiji14@users.noreply.github.com>

Author: seisman

pygmt/params/box.py

@@ -27,15 +27,15 @@ class Box(BaseParam):
         - a sequence of four values means separate clearances for left/right/bottom/top.
     fill
         Fill for the box [Default is no fill].
+    inner_gap
+        Gap between the outer and inner borders [Default is ``"2p"``].
+    inner_pen
+        Pen attributes for the inner border [Default to :gmt-term:`MAP_DEFAULT_PEN`].
     pen
         Pen attributes for the box outline.
     radius
         Draw a rounded rectangular border instead of sharp. Passing a value with unit
         to control the corner radius [Default is ``"6p"``].
-    inner_gap
-        Gap between the outer and inner borders [Default is ``"2p"``].
-    inner_pen
-        Pen attributes for the inner border [Default to :gmt-term:`MAP_DEFAULT_PEN`].
     shade_offset
         Place an offset background shaded region behind the box. A sequence of two
         values (dx, dy) indicates the shift relative to the foreground frame [Default is