feat: add CSP and other security related headers in the oCIS proxy service (#8777)

* feat: add CSP and other security related headers in the oCIS proxy service

* fix: consolidate security related headers - drop middleware.Secure

* fix: use github.com/DeepDiver1975/secure

* fix: acceptance tests

* feat: support env var replacements in csp.yaml

services/idp/pkg/server/http/server.go

@@ -61,7 +61,6 @@ func Server(opts ...Option) (http.Service, error) {
 			chimiddleware.RequestID,
 			middleware.TraceContext,
 			middleware.NoCache,
-			middleware.Secure,
 			middleware.Version(
 				options.Config.Service.Name,
 				version.GetString(),