[misc] Separate shared code dependencies (#4288)

* Separate shared code dependencies

* Fix import

* Test respective shared code

* Update openapi ref

* Fix test

* Fix test path

shared/relay/tls/client_prod.go

@@ -0,0 +1,25 @@
+//go:build !devcert
+
+package tls
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+
+	log "github.com/sirupsen/logrus"
+
+	"github.com/netbirdio/netbird/util/embeddedroots"
+)
+
+func ClientQUICTLSConfig() *tls.Config {
+	certPool, err := x509.SystemCertPool()
+	if err != nil || certPool == nil {
+		log.Debugf("System cert pool not available; falling back to embedded cert, error: %v", err)
+		certPool = embeddedroots.Get()
+	}
+
+	return &tls.Config{
+		NextProtos: []string{nbalpn},
+		RootCAs:    certPool,
+	}
+}