chore: Export codegen parseFile function (#35000)

Summary:
This PR export the content of the `parseFile` into a parseFile function accepting a callback to buildSchema properly in `parsers/utils.js` as requested on https://github.com/facebook/react-native/issues/34872.

## Changelog

[Internal] [Changed] - Export ` parseFile` in to a `parseFile` function in `parsers/utils.js`

Pull Request resolved: https://github.com/facebook/react-native/pull/35000

Test Plan:
Run `yarn jest react-native-codegen` and ensure CI is green

![image](https://user-images.githubusercontent.com/11707729/196051689-1b61838c-477c-4be5-8df0-9f5969fcf90d.png)

Reviewed By: cortinico

Differential Revision: D40424857

Pulled By: cipolleschi

fbshipit-source-id: a700033d674b8be8e1af942dedf73155ea3ca025

packages/react-native-codegen/e2e/__tests__/components/GeneratePropsJavaInterface-test.js

@@ -11,7 +11,8 @@
 
 'use strict';
 
-const parser = require('../../../src/parsers/flow');
+const {parseFile} = require('../../../src/parsers/utils');
+const FlowParser = require('../../../src/parsers/flow');
 const generator = require('../../../src/generators/components/GeneratePropsJavaInterface');
 const fs = require('fs');
 
@@ -21,7 +22,10 @@ const fixtures = fs.readdirSync(FIXTURE_DIR);
 fixtures.forEach(fixture => {
   it(`GeneratePropsJavaInterface can generate for '${fixture}'`, () => {
     const libName = 'RNCodegenModuleFixtures';
-    const schema = parser.parseFile(`${FIXTURE_DIR}/${fixture}`);
+    const schema = parseFile(
+      `${FIXTURE_DIR}/${fixture}`,
+      FlowParser.buildSchema,
+    );
     const output = generator.generate(libName, schema, undefined, false);
     expect(Object.fromEntries(output)).toMatchSnapshot();
   });