lingo: remove webservice URL trailing slash if necessary (#10347)

combo/apps/lingo/models.py

@@ -86,6 +86,11 @@ class Regie(models.Model):
     class Meta:
         verbose_name = _('Regie')
 
+    def save(self, *args, **kwargs):
+        if self.webservice_url and self.webservice_url.endswith('/'):
+            self.webservice_url = self.webservice_url.strip('/')
+        super(Regie, self).save(*args, **kwargs)
+
     def natural_key(self):
         return (self.slug,)