Updated icons

Author: andrey-helldar

docs/topics/introduction.topic

@@ -21,10 +21,10 @@
         <primary>
             <title>Guide</title>
 
-            <a href="running-operations.topic" type="academy" />
-            <a href="creating-operations.topic" type="world" />
-            <a href="rolling-back-operations.topic" type="navigation" />
-            <a href="operations-status.topic" type="library" />
+            <a href="running-operations.topic" type="start" />
+            <a href="creating-operations.topic" type="tools" />
+            <a href="rolling-back-operations.topic" type="turn-on" />
+            <a href="operations-status.topic" type="check-list" />
         </primary>
 
         <secondary>