Add hermes parser (#17520)

CONTRIBUTING.md

@@ -48,7 +48,7 @@ function runFormatTest(
 Parameters:
 
 - **`fixtures`**: Must be set to `import.meta` or to an object of the shape `{ importMeta: import.meta, ... }`. The object may have the `snippets` property to specify an array of extra input entries in addition to the files in the current directory. For each input entry (a file or a snippet), `runFormatTest` configures and runs a number of tests. The main check is that for a given input the output should match the snapshot (for snippets, the expected output can also be specified directly). [Additional checks](#deeper-testing) are controlled by options and environment variables.
-- **`parsers`**: A list of parser names. The tests verify that the parsers in this list produce the same output. If the list includes `typescript`, then `babel-ts`, and `oxc-ts` is included implicitly. If the list includes `flow`, then `babel-flow` is included implicitly. If the list includes `babel`, and the current directory is inside `tests/format/js` or `tests/format/jsx`, then `acorn`, `espree`, `meriyah`, and `oxc` are included implicitly.
+- **`parsers`**: A list of parser names. The tests verify that the parsers in this list produce the same output. If the list includes `typescript`, then `babel-ts`, and `oxc-ts` are included implicitly. If the list includes `flow`, then `hermes` and `babel-flow` is included implicitly. If the list includes `babel`, and the current directory is inside `tests/format/js` or `tests/format/jsx`, then `acorn`, `espree`, `meriyah`, and `oxc` are included implicitly.
 - **`options`**: In addition to Prettier's formatting options, can contain the `errors` property to specify that it's expected that the formatting shouldn't be successful and an error should be thrown for all (`errors: true`) or some combinations of input entries and parsers.
 
 The implementation of `runFormatTest` can be found in [`tests/config/run-format-test.js`](tests/config/run-format-test.js).