search-in-workspace: add noselect to line result nodes

The commit adds `noselect` to the line result nodes so thier inner text
is not selectable, aligning with the rest of the framework and vscode.

packages/search-in-workspace/src/browser/search-in-workspace-result-tree-widget.tsx

@@ -1004,7 +1004,7 @@ export class SearchInWorkspaceResultTreeWidget extends TreeWidget {
             after = node.lineText.text.substr(node.lineText.character + node.length);
             title = node.lineText.text.trim();
         }
-        return <div className={`resultLine noWrapInfo ${node.selected ? 'selected' : ''}`} title={title}>
+        return <div className={`resultLine noWrapInfo noselect ${node.selected ? 'selected' : ''}`} title={title}>
             {this.searchInWorkspacePreferences['search.lineNumbers'] && <span className='theia-siw-lineNumber'>{node.line}</span>}
             <span>
                 {before}