Redact sensitive values from config in health data (#12421)

The health api returns the server configuration details. Redact
sensitive values from the config values like URLs and credentials.

internal/config/etcd/help.go

@@ -26,6 +26,7 @@ var (
 			Key:         Endpoints,
 			Description: `comma separated list of etcd endpoints e.g. "http://localhost:2379"`,
 			Type:        "csv",
+			Sensitive:   true,
 		},
 		config.HelpKV{
 			Key:         PathPrefix,
@@ -44,12 +45,14 @@ var (
 			Description: `client cert for mTLS authentication`,
 			Optional:    true,
 			Type:        "path",
+			Sensitive:   true,
 		},
 		config.HelpKV{
 			Key:         ClientCertKey,
 			Description: `client cert key for mTLS authentication`,
 			Optional:    true,
 			Type:        "path",
+			Sensitive:   true,
 		},
 		config.HelpKV{
 			Key:         config.Comment,