Directly push 'this' to LayerSelector.objects

Instead of creating a variable beforehand. It seems like 'self' was
not used anywhere else. Remove variable 'self' as it was not used

src/js/gui/Button/ShareView.js

@@ -133,7 +133,5 @@ import { Utils } from "../../Utils";
             },
             tooltip: {content: 'You can share/export your view into many ways', position: {direction: 'top'}},
         }, aladin);
-
-        self = this;
     }
 }

src/js/gui/Input/LayerSelector.js

@@ -80,9 +80,7 @@ export class LayerSelector extends Input {
             ...options
         })
 
-        self = this;
-
-        LayerSelector.objects.push(self);
+        LayerSelector.objects.push(this);
     }
 };