Add full-stop period

GenericMappingTools · willschlitzer · Jan 2, 2021 · Jan 21, 2021 · Jan 21, 2021 · Jan 21, 2021
commit 0d6180faeaef44de2befcaeddea94fec9030da23
diff --git a/pygmt/helpers/decorators.py b/pygmt/helpers/decorators.py
@@ -20,7 +20,7 @@
             is the first plot command.""",
     "J": """\
         projection : str
-            *projection*\ [*projection-specific arguments*\ ]*figure size*
+            *projection*\ [*projection-specific arguments*\ ]*figure size*.
             Select map projection. This is a required argument if this 
             is the first plot command.""",
     "B": """\