wcs: make sure there's a / after the domain name (#7320)

combo/apps/wcs/models.py

@@ -147,6 +147,8 @@ class WcsBlurpMixin(object):
         sources = []
         for slug, wcs_site in wcs_sites.items():
             url = wcs_site.get('url')
+            if not url.endswith('/'):
+                url += '/'
             source = {
                 'slug': slug,
                 'parser_type': 'json',