[ermine] Remove logout button keyboard shortcut help text

The logout button does not exist in ermine anymore, but we have a
leftover mention of it in the keyboard shortcuts help text. This
change removes it.

Bug: 60056
Test: All tests pass.

Change-Id: I3ee00aafbe9111c555ee1b6f2ee1343ed7330f4d
Reviewed-on: https://fuchsia-review.googlesource.com/c/experiences/+/427915
Reviewed-by: Charles Whitten <cwhitten@google.com>
Testability-Review: Sanjay Chouksey <sanjayc@google.com>
Commit-Queue: Sanjay Chouksey <sanjayc@google.com>
diff --git a/session_shells/ermine/shell/config/keyboard_shortcuts.json b/session_shells/ermine/shell/config/keyboard_shortcuts.json
index 532204e..837cc27 100644
--- a/session_shells/ermine/shell/config/keyboard_shortcuts.json
+++ b/session_shells/ermine/shell/config/keyboard_shortcuts.json
@@ -88,13 +88,5 @@
       "chord": "Meta + <-",
       "description": "Previous cluster"
     }
-  ],
-  "logout": [
-    {
-      "char": "o",
-      "modifier": "alt",
-      "chord": "Alt + o",
-      "description": "Logout session"
-    }
   ]
-}
\ No newline at end of file
+}