fix(style): align navbar-toggle

Changes:
- change `.navbar-toggle` from `margin: 0 -15px 0 0;` to `margin: 0;`

CHANGELOG

@@ -7,6 +7,7 @@ v 7.10.0 (unreleased)
   - List new commits for newly pushed branch in activity view.
   - Add changelog, license and contribution guide links to project sidebar.
   - Improve diff UI
+  - Fix alignment of navbar toggle button (Cody Mize)
   - Identical look of selectboxes in UI
 
 v 7.9.0 (unreleased)

app/assets/stylesheets/pages/header.scss

@@ -31,7 +31,7 @@ header {
 
       .navbar-toggle {
         color: $style_color;
-        margin: 0 -15px 0 0;
+        margin: 0;
         padding: 10px;
         border-radius: 0;