Update PROCESS.md

Co-authored-by: Julian Berman <Julian@GrayVines.com>

Author: jdesrosiers

PROCESS.md

@@ -156,7 +156,7 @@ are subject to the same compatibility rules as the specification. They can be
 updated at any time, but changes MUST be backward compatible and allow for
 forward compatibility with future schemas.
 
-Meta-schema URIs SHOULD not change once published, but if they do, the old URI
+Meta-schema URIs SHOULD NOT change once published, but if they do, the old URI
 MUST remain available and redirect to the new URI.
 
 Meta-schemas are considered non-normative. It's sometimes not possible or not