[meld] Fix Gitlab release tagging

[Kai Willadsen <kaiw src gnome org>]

commit 3aa85b48174b4403b349fc270cbe8132b7c854c4
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Wed Mar 28 10:05:36 2018 +1000

    Fix Gitlab release tagging
    
    Look what you find when you run things in anger!

 maint | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)
---
diff --git a/maint b/maint
index aef45d79..e7462a74 100755
--- a/maint
+++ b/maint
@@ -2,7 +2,6 @@
 
 import collections
 import datetime
-import json
 import os
 import re
 import subprocess
@@ -312,7 +311,7 @@ def gitlab_release_tag(tag):
                 id=GITLAB_PROJECT_ID)
         )
 
-    cmd = ['git', 'tag', '-l', "--format='%(contents)'", tag]
+    cmd = ['git', 'tag', '-l', "--format=%(contents)", tag]
     description = subprocess.check_output(cmd).decode('utf-8')
 
     endpoint = '{base}/projects/{id}/repository/tags/{tag_name}/release'
@@ -329,13 +328,18 @@ def gitlab_release_tag(tag):
     # TODO: Should probably sanity-check that it's not already a
     # release tag.
 
-    requests.post(
+    response = requests.post(
         release_url,
-        data=json.dumps(release_data),
+        json=release_data,
         headers={
             'Private-Token': auth_token,
         },
     )
+    try:
+        response.raise_for_status()
+    except Exception as e:
+        click.secho(
+            'Error making release: {}\n{}'.format(e, response.text), fg='red')
 
 
 @click.group()