Update request.md (#712)

mention API Shield on tlsClientAuth

Author: eidam

products/workers/src/content/runtime-apis/request.md

@@ -215,7 +215,7 @@ All plans have access to:
 
 - `tlsClientAuth` <Type>Object | null</Type>
 
-  - Only set when using Cloudflare Access. Object with the following properties: `certIssuerDNLegacy`, `certIssuerDN`, `certIssuerDNRFC2253`, `certSubjectDNLegacy`, `certVerified`, `certNotAfter`, `certSubjectDN`, `certFingerprintSHA1`, `certNotBefore`, `certSerial`, `certPresented`, `certSubjectDNRFC2253`.
+  - Only set when using Cloudflare Access or API Shield. Object with the following properties: `certIssuerDNLegacy`, `certIssuerDN`, `certIssuerDNRFC2253`, `certSubjectDNLegacy`, `certVerified`, `certNotAfter`, `certSubjectDN`, `certFingerprintSHA1`, `certNotBefore`, `certSerial`, `certPresented`, `certSubjectDNRFC2253`.
 
 - `tlsVersion` <Type>string</Type>