[gnome-builder] greeter: fix back button to use go-previous-symbolic

[Christian Hergert <chergert src gnome org>]

commit 11a08261ff68a7e76a53736b62f8d80f953d5401
Author: Christian Hergert <chergert redhat com>
Date:   Wed Jan 16 11:13:17 2019 -0800

    greeter: fix back button to use go-previous-symbolic
    
    Fixes #758

 src/libide/greeter/ide-greeter-workspace.ui | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/src/libide/greeter/ide-greeter-workspace.ui b/src/libide/greeter/ide-greeter-workspace.ui
index b63f2a37d..e36fc25ee 100644
--- a/src/libide/greeter/ide-greeter-workspace.ui
+++ b/src/libide/greeter/ide-greeter-workspace.ui
@@ -15,10 +15,13 @@
             <property name="has-tooltip">true</property>
             <property name="tooltip-text" translatable="yes">Go back</property>
             <property name="margin-end">6</property>
+            <style>
+              <class name="image-button"/>
+            </style>
             <child>
               <object class="GtkImage">
                 <property name="visible">true</property>
-                <property name="icon-name">pan-start-symbolic</property>
+                <property name="icon-name">go-previous-symbolic</property>
               </object>
             </child>
           </object>