move all plugin tests out of babel-core and into their appropriate folders

packages/babel-plugin-transform-react-inline-elements/test/fixtures/inline-elements/key/expected.js

@@ -0,0 +1,10 @@
+({
+  $$typeof: babelHelpers.typeofReactElement,
+  type: Foo,
+  key: "foo",
+  ref: null,
+  props: babelHelpers.defaultProps(Foo.defaultProps, {
+    "data-value": "bar"
+  }),
+  _owner: null
+});