Remove old Orbit in Oomph p2 repo from setup (#524)

The https://download.eclipse.org/oomph/simrel-orbit/ was the temporary
URL.

Author: jonahgraham

releng/CDT.setup

@@ -245,8 +245,6 @@
             url="https://download.eclipse.org/tools/cdt/releases/latest"/>
         <repository
             url="https://download.eclipse.org/tools/orbit/simrel/orbit-aggregation/2023-09"/>
-        <repository
-            url="https://download.eclipse.org/oomph/simrel-orbit/milestone/latest/"/>
         <repository
             url="https://download.eclipse.org/technology/swtbot/releases/latest"/>
         <repository