mkhtml.py: catch Python-3.6 unicode error in escape_href() for lib/init/helptext.html

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@74044 15284696-431f-4ddb-bdfa-cd5b030d7da7

tools/mkhtml.py

@@ -241,6 +241,7 @@ def write_toc(data):
                 fd.write('%s</ul></li>\n' % (' ' * indent))
                 in_h3 = False
 
+        text = text.replace(u'\xa0', u' ')
         fd.write('%s<li class="toc"><a href="#%s" class="toc">%s</a>' % \
                      (' ' * indent, escape_href(text), text))
         first = False