Fixed plugin installer overflow (#2652)

Summary:
https://user-images.githubusercontent.com/33036510/127777930-34ede219-0fb9-4486-8f2e-3d73ff8cb84d.mov

Content of plugin installer modal has no scroll and it is overflowing

## Changelog

- Fixed PluginInstaller table overflow

Pull Request resolved: https://github.com/facebook/flipper/pull/2652

Test Plan:
The video, demonstrating how the problem was fixed:
https://user-images.githubusercontent.com/33036510/127777930-34ede219-0fb9-4486-8f2e-3d73ff8cb84d.mov

Reviewed By: passy

Differential Revision: D30044703

Pulled By: cekkaewnumchai

fbshipit-source-id: 6d00ef766aaa295cc43fd944ca3b849371192a79

desktop/app/src/chrome/plugin-manager/PluginInstaller.tsx

@@ -118,6 +118,7 @@ const PluginInstaller = function ({
         highlightedRows={new Set()}
         autoHeight={autoHeight}
         rows={rows}
+        horizontallyScrollable
       />
       <PluginPackageInstaller onInstall={onInstall} />
     </Layout.Container>