Update test expected strings for net9

Author: oscarsj

csharp/ql/integration-tests/all-platforms/autobuild/Files.expected

@@ -1,3 +1,3 @@
 | Program.cs:0:0:0:0 | Program.cs |
-| obj/Debug/net5.0/.NETCoreApp,Version=v5.0.AssemblyAttributes.cs:0:0:0:0 | obj/Debug/net5.0/.NETCoreApp,Version=v5.0.AssemblyAttributes.cs |
-| obj/Debug/net5.0/autobuild.AssemblyInfo.cs:0:0:0:0 | obj/Debug/net5.0/autobuild.AssemblyInfo.cs |
+| obj/Debug/net9.0/.NETCoreApp,Version=v9.0.AssemblyAttributes.cs:0:0:0:0 | obj/Debug/net9.0/.NETCoreApp,Version=v5.0.AssemblyAttributes.cs |
+| obj/Debug/net9.0/autobuild.AssemblyInfo.cs:0:0:0:0 | obj/Debug/net9.0/autobuild.AssemblyInfo.cs |