Update example to use type specifier

Co-authored-by: Josh Mandel <[email protected]>

input/pagecontent/StructureDefinition-ViewDefinition-notes.md

@@ -51,7 +51,7 @@ be equal to the [getResourceKey()](#getresourcekey--keytype) value returned on t
 Users may pass an optional resource type (e.g. `Patient` or `Observation`) to indicate
 the expected type that the reference should point to. `getReferenceKey` will return an empty collection 
 (effectively `null` since FHIRPath always returns collections) if the reference is not of the 
-expected type. For example, `Observation.subject.getReferenceKey('Patient')` would return a row key if the
+expected type. For example, `Observation.subject.getReferenceKey(Patient)` would return a row key if the
 subject is a patient, or the empty collection (`{}`) if not. 
 
 Implementations MUST support the relative literal form of reference (e.g. `Patient/123`), and MAY support