Merge pull request #2418 from rhamilto/monitoring-sidebar-heading

Automatic merge from submit-queue.

Adjust spacing around 'Events' heading in sidebar on monitoring page

In #2389 I adjusted the spacing around the h1 so borders aligned, but I overlooked the border underneath "Events" in the monitoring page sidebar.  This fixes that, and does so in a way that the border is consistent across browsers (it wasn't before--only Chrome had a correctly aligned border).

Before:
![screen shot 2017-11-01 at 10 46 26 am](https://user-images.githubusercontent.com/895728/32280359-f7445e58-bef1-11e7-9765-d61c6e7fe48f.PNG)

After:
![screen shot 2017-11-01 at 10 46 01 am](https://user-images.githubusercontent.com/895728/32280352-f404cbec-bef1-11e7-9c82-620523fe5814.PNG)

app/styles/_sidebar-right.less

@@ -139,10 +139,13 @@
     display: flex;
     justify-content: space-between;
     // So that sidebar bottom border aligns with main content header bottom border.
-    margin-top: 17.5px;
+    margin-top: 0;
+    padding-bottom: 21px;
+    padding-top: 24px;
     h2 {
-      .h4();
-      display: inline-block;
+      font-size: 14px;
+      margin-bottom: 0;
+      margin-top: 0;
     }
     .warning-count {
       .nowrap();