fix the matching of archivetypes

updated query came from mikem in https://pagure.io/koji/issue/10

Signed-off-by: Dennis Gilmore <dennis@ausil.us>

hub/kojihub.py

@@ -5400,7 +5400,7 @@ def get_archive_type(filename=None, type_name=None, type_id=None, strict=False):
         ext = '.'.join(parts[start:])
 
         select = r"""SELECT id, name, description, extensions FROM archivetypes
-                      WHERE extensions ~ E'\\m%s\\M'""" % ext
+                      WHERE extensions ~* E'(\\s|^)%s(\\s|$)'""" % ext
         results = _multiRow(select, locals(), ('id', 'name', 'description', 'extensions'))
 
         if len(results) == 1: