Adjust spacing, remove button icons

contribute.html

@@ -10,29 +10,20 @@ office_hours_link: https://github.zoom.us/j/221410810
     We're thrilled that you'd like to contribute to this project. Your help is essential for keeping it great.
   </p>
 
-  <div class="d-flex gutter featurette text-center">
-    <div class="col-4 text-center">
-      <a class="btn btn-outline" href="https://probot-slackin.herokuapp.com/">
-        {% octicon comment-discussion class:"mr-1" %}
-        Chat on Slack
-      </a>
-    </div>
-
-    <div class="col-4 text-center">
-      <a class="btn btn-outline" href="https://github.com/probot/probot">
-        {% octicon mark-github class:"mr-1" %}
-        Contribute on GitHub
-      </a>
-    </div>
-
-    <div class="col-4 text-center">
-      <a class="btn btn-outline" href="https://twitter.com/ProbotTheRobot">
-        Follow on Twitter
-      </a>
-    </div>
+  <div class="text-center mt-6">
+    <a class="btn btn-outline mr-2" href="https://probot-slackin.herokuapp.com/">
+      Chat on Slack
+    </a>
+  
+    <a class="btn btn-outline mr-2" href="https://github.com/probot/probot">
+      Contribute on GitHub
+    </a>
+  
+    <a class="btn btn-outline" href="https://twitter.com/ProbotTheRobot">
+      Follow on Twitter
+    </a>
   </div>
 
-
   <div id="office-hours" class="d-md-flex flex-row-reverse my-6">
     <div class="col-md-6 flex-md-self-center">
       <h2 class="alt-h3">Office Hours</h2>