Fix .information-board style for Safari (#4602)

flex-basis: 0 allows make flexbox smaller than its contents on Safari <10.

https://github.com/philipwalton/flexbugs#1-minimum-content-sizing-of-flex-items-not-honored

app/javascript/styles/about.scss

@@ -171,7 +171,7 @@
   }
 
   .section {
-    flex: 1 0 0;
+    flex: 1 0 auto;
     font: 16px/28px 'mastodon-font-sans-serif', sans-serif;
     text-align: right;
     padding: 10px 15px;