Enable external-helpers by default in tests (#12911)

Co-authored-by: Huáng Jùnliàng <jlhwung@gmail.com>
Co-authored-by: Babel Bot <babel-bot@users.noreply.github.com>

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration-loose/options.json

@@ -3,7 +3,6 @@
     "proposal-class-static-block",
     ["proposal-private-property-in-object", { "loose": true }],
     ["proposal-private-methods", { "loose": true }],
-    ["proposal-class-properties", { "loose": true }],
-    "external-helpers"
+    ["proposal-class-properties", { "loose": true }]
   ]
 }

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/name-conflict/output.js

@@ -1,5 +1,3 @@
-function _classStaticPrivateFieldSpecGet(receiver, classConstructor, descriptor) { if (receiver !== classConstructor) { throw new TypeError("Private static access of wrong provenance"); } if (descriptor.get) { return descriptor.get.call(receiver); } return descriptor.value; }
-
 class Foo {}
 
 var _ = {
@@ -9,7 +7,7 @@ var _ = {
 var _2 = {
   writable: true,
   value: (() => {
-    Foo.foo = _classStaticPrivateFieldSpecGet(Foo, Foo, _);
+    Foo.foo = babelHelpers.classStaticPrivateFieldSpecGet(Foo, Foo, _);
   })()
 };
 expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/options.json

@@ -3,7 +3,6 @@
     "proposal-class-static-block",
     "proposal-private-property-in-object",
     "proposal-private-methods",
-    "proposal-class-properties",
-    "external-helpers"
+    "proposal-class-properties"
   ]
 }