wxGUI: fix typo introduced in https://trac.osgeo.org/grass/changeset/49915

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@49916 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/xml/menudata.xml

@@ -895,7 +895,7 @@
 	      <help>Rebuilds all locally installed GRASS Addons extensions.</help>
 	      <keywords>general,installation,extensions</keywords>
 	      <handler>OnMenuCmd</handler>
-	      <command>g.extension.rebuild.all.py</command>
+	      <command>g.extension.rebuild.all</command>
 	    </menuitem>
 	    <menuitem>
 	      <label>Remove extension</label>