fix(AIP-203): remove required-and-optional rule (#1178)

Author: noahdietz

docs/rules/0203/required-and-optional.md

@@ -39,7 +39,6 @@ func AddRules(r lint.RuleRegistry) error {
 		optionalBehaviorConflict,
 		outputOnly,
 		required,
-		requiredAndOptional,
 		unorderedListRepeated,
 	)
 }