cleanup: Remove empty leading/trailing lines in blocks

gjs added a new rule to its eslint ruleset that forbids "block padding",
so make sure we conform to that rule before syncing up the configuration.

https://gitlab.gnome.org/GNOME/gnome-shell-extensions/-/merge_requests/137

extensions/native-window-placement/extension.js

@@ -103,7 +103,6 @@ class NaturalLayoutStrategy extends Workspace.LayoutStrategy {
             direction++;
             if (direction === 4)
                 direction = 0;
-
         }
 
         let loopCounter = 0;

extensions/places-menu/placeDisplay.js

@@ -486,7 +486,6 @@ var PlacesManager = class {
     }
 
     _reloadBookmarks() {
-
         this._bookmarks = [];
 
         let content = Shell.get_file_contents_utf8_sync(this._bookmarksFile.get_path());

extensions/window-list/extension.js

@@ -612,7 +612,6 @@ class AppButton extends BaseButton {
             this._contextMenuManager.addMenu(this._appContextMenu);
             this.label_actor = this._multiWindowTitle.label_actor;
         }
-
     }
 
     _onClicked(actor, button) {