Add missing Symbol.split feature flags

test/built-ins/RegExp/prototype/Symbol.split/length.js

@@ -14,6 +14,7 @@ info: >
     object has the attributes { [[Writable]]: false, [[Enumerable]]: false,
     [[Configurable]]: true }.
 includes: [propertyHelper.js]
+features: [Symbol.split]
 ---*/
 
 assert.sameValue(RegExp.prototype[Symbol.split].length, 2);

test/built-ins/RegExp/prototype/Symbol.split/name.js

@@ -14,6 +14,7 @@ info: >
     object, if it exists, has the attributes { [[Writable]]: false,
     [[Enumerable]]: false, [[Configurable]]: true }.
 includes: [propertyHelper.js]
+features: [Symbol.split]
 ---*/
 
 assert.sameValue(RegExp.prototype[Symbol.split].name, '[Symbol.split]');

test/built-ins/RegExp/prototype/Symbol.split/splitter-proto-from-ctor-realm.js

@@ -15,7 +15,7 @@ info: >
        a. Let realm be ? GetFunctionRealm(constructor).
        b. Let proto be realm's intrinsic object named intrinsicDefaultProto.
     [...]
-features: [Symbol.species]
+features: [Symbol.species, Symbol.split]
 ---*/
 
 var other = $262.createRealm().global;