update badges for ionic gz-gui9 (#636)

Signed-off-by: Jenn Nguyen <jennuine@intrinsic.ai>

Author: jennuine

README.md

@@ -9,10 +9,10 @@
 
 Build | Status
 -- | --
-Test coverage | [![codecov](https://codecov.io/gh/gazebosim/gz-gui/branch/main/graph/badge.svg)](https://codecov.io/gh/gazebosim/gz-gui/branch/main)
-Ubuntu Noble| [![Build Status](https://build.osrfoundation.org/buildStatus/icon?job=gz_gui-ci-main-noble-amd64)](https://build.osrfoundation.org/job/gz_gui-ci-main-noble-amd64)
-Homebrew      | [![Build Status](https://build.osrfoundation.org/buildStatus/icon?job=gz_gui-ci-main-homebrew-amd64)](https://build.osrfoundation.org/job/gz_gui-ci-main-homebrew-amd64)
-Windows       | [![Build Status](https://build.osrfoundation.org/buildStatus/icon?job=gz_gui-main-win)](https://build.osrfoundation.org/job/gz_gui-main-win)
+Test coverage | [![codecov](https://codecov.io/gh/gazebosim/gz-gui/tree/gz-gui9/graph/badge.svg)](https://codecov.io/gh/gazebosim/gz-gui/tree/gz-gui9)
+Ubuntu Noble| [![Build Status](https://build.osrfoundation.org/buildStatus/icon?job=gz_gui-ci-gz-gui9-noble-amd64)](https://build.osrfoundation.org/job/gz_gui-ci-gz-gui9-noble-amd64)
+Homebrew      | [![Build Status](https://build.osrfoundation.org/buildStatus/icon?job=gz_gui-ci-gz-gui9-homebrew-amd64)](https://build.osrfoundation.org/job/gz_gui-ci-gz-gui9-homebrew-amd64)
+Windows       | [![Build Status](https://build.osrfoundation.org/buildStatus/icon?job=gz_gui-9-win)](https://build.osrfoundation.org/job/gz_gui-9-win)
 
 Gazebo GUI builds on top of [Qt](https://www.qt.io/) to provide widgets which are
 useful when developing robotics applications, such as a 3D view, plots, dashboard, etc,