Plugin auto-fix can't handle empty function

[pedr]

I don't think this is a very useful edge case, but I found this error running the plugin.

Returning undefined resolves the problem.

.eslintrs.js

module.exports = {
    'parserOptions': {
        'ecmaVersion': 2018,
        'sourceType': 'module',
    },
    'plugins': [
        'prefer-arrow-functions',
    ],
    'rules': {
        'prefer-arrow-functions/prefer-arrow-functions': [
            'error',
            {
                'classPropertiesAllowed': false,
                'disallowPrototype': true,
                'returnStyle': 'unchanged',
                'singleReturnOnly': true,
            },
        ],
    },
};

file.js

function test() {
    return;
}

Try to run:

yarn eslint --fix --plugin prefer-arrow-functions file.js 

Error found:

TypeError: Cannot read properties of null (reading 'type')
Occurred while linting /home/pedr/repo/eslint-plugin-prefer-arrow/file.js:1
    at getBodySource (/home/pedr/repo/eslint-plugin-prefer-arrow/node_modules/eslint-plugin-prefer-arrow-functions/dist/prefer-arrow-functions.js:57:36)
    at getFunctionDescriptor (/home/pedr/repo/eslint-plugin-prefer-arrow/node_modules/eslint-plugin-prefer-arrow-functions/dist/prefer-arrow-functions.js:128:23)
    at writeArrowConstant (/home/pedr/repo/eslint-plugin-prefer-arrow/node_modules/eslint-plugin-prefer-arrow-functions/dist/prefer-arrow-functions.js:121:24)
    at Object.fix (/home/pedr/repo/eslint-plugin-prefer-arrow/node_modules/eslint-plugin-prefer-arrow-functions/dist/prefer-arrow-functions.js:243:60)
    at normalizeFixes (/home/pedr/repo/eslint-plugin-prefer-arrow/node_modules/eslint/lib/linter/report-translator.js:178:28)
    at /home/pedr/repo/eslint-plugin-prefer-arrow/node_modules/eslint/lib/linter/report-translator.js:343:49
    at Object.report (/home/pedr/repo/eslint-plugin-prefer-arrow/node_modules/eslint/lib/linter/linter.js:905:41)
    at FunctionDeclaration[parent.type!="ExportDefaultDeclaration"] (/home/pedr/repo/eslint-plugin-prefer-arrow/node_modules/eslint-plugin-prefer-arrow-functions/dist/prefer-arrow-functions.js:241:29)
    at /home/pedr/repo/eslint-plugin-prefer-arrow/node_modules/eslint/lib/linter/safe-emitter.js:45:58
    at Array.forEach (<anonymous>)
error Command failed with exit code 2.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.