Add Wall of Browser Bugs entry for #18543

https://connect.microsoft.com/IE/feedback/details/2256049/edge-ie11-viewport-rule-has-side-effect-of-making-scrollbars-auto-hide
[ci skip]

docs/_data/browser-bugs.yml

@@ -38,6 +38,16 @@
   origin: >
     Bootstrap#18504
 
+-
+  browser: >
+    Internet Explorer 11 & Microsoft Edge
+  summary: >
+    `@-ms-viewport{width: device-width;}` has side-effect of making scrollbars auto-hide
+  upstream_bug: >
+    IE#2256049
+  origin: >
+    Bootstrap#18543
+
 -
   browser: >
     Firefox