JetBrains: remove icons from the groups (#55068)

remove icons from the groups as they're not supported and not consistent
with the rest of the ui
No update to the changelog because this doesn't change anything in our
plugin

## Test plan
- Green CI

<!-- All pull requests REQUIRE a test plan:
https://docs.sourcegraph.com/dev/background-information/testing_principles
-->

Author: Szymon Przebierowski

client/jetbrains/src/main/resources/META-INF/plugin.xml

@@ -196,7 +196,7 @@
             <reference ref="cody.refreshCodyAppDetection"/>
         </group>
 
-        <group id="CodyEditorActions" icon="/icons/codyLogoSm.svg" popup="true" text="Cody"
+        <group id="CodyEditorActions" popup="true" text="Cody"
                searchable="false" class="com.sourcegraph.cody.CodyActionGroup">
             <reference ref="cody.downloadAndInstallCodyAction"/>
             <reference ref="cody.runCodyAppAction"/>
@@ -210,7 +210,7 @@
             <add-to-group anchor="last" group-id="EditorPopupMenu"/>
         </group>
 
-        <group id="SourcegraphEditor" icon="/icons/sourcegraphLogo.svg" popup="true" text="Sourcegraph"
+        <group id="SourcegraphEditor" popup="true" text="Sourcegraph"
                searchable="false">
             <reference ref="sourcegraph.openFindPopup"/>
             <reference ref="sourcegraph.searchSelection"/>