Update documentation/CAMARA-Security-Interoperability.md

Co-authored-by: Eric Murray <[email protected]>

documentation/CAMARA-Security-Interoperability.md

@@ -112,7 +112,7 @@ This CAMARA document clarifies the values used in login_hint in the following wa
 
     For operator tokens as defined by [GSMA TS.43](https://www.gsma.com/newsroom/gsma_resources/ts-43-service-entitlement-configuration/) and [GSMA ASAC](https://www.gsma.com/newsroom/gsma_resources/asac-01-v1-0/).
     TS.43 does not specify the format of the operator token and it therefore might contain characters that are not url-safe.
-    This document specifies that the API consumer must encode the operator token using [base64url](https://www.rfc-editor.org/rfc/rfc7515.html#appendix-C) encoding to make it urlsafe.
+    The API consumer MUST encode the operator token using [base64url](https://www.rfc-editor.org/rfc/rfc7515.html#appendix-C) encoding to make it URL safe.
     For example, `operatortoken:ZXhhbXBsZQ`
 
    This document does not specifiy how the API consumer got the operatorToken.