chore: Use upstream cinder to build container images

Since all patches have been merged upstream, there is no longer a need
to use the forked repository. To reduce technical debt, we can remove
Cinder from the list of forked repositories.
diff --git a/internal/pkg/image_repositories/build_workflow.go b/internal/pkg/image_repositories/build_workflow.go
index 658f8cd..1d48e3f 100644
--- a/internal/pkg/image_repositories/build_workflow.go
+++ b/internal/pkg/image_repositories/build_workflow.go
@@ -6,7 +6,6 @@
 )
 
 var FORKED_PROJECTS map[string]bool = map[string]bool{
-	"cinder":   true,
 	"horizon":  true,
 	"keystone": true,
 	"magnum":   true,