fix: only delete if editorsMinimaps is not null

Author: aminya

lib/minimap.js

@@ -269,7 +269,9 @@ export default class Minimap {
       }),
 
       this.textEditor.onDidDestroy(() => {
-        editorsMinimaps.delete(this.textEditor)
+        if (editorsMinimaps) {
+          editorsMinimaps.delete(this.textEditor)         
+        }
         this.destroy()
       }),