fix(version): Fix file formatting on git add

[BenoitZugmeyer]

Description

PR #3766 brought prettier 3 support by using asynchronous prettier APIs, but missed one await when calling .format(...).

Because of this, fs.writeFileSync(...) is called with a Promise instead of a string and throws an exception:

TypeError [ERR_INVALID_ARG_TYPE]: The "data" argument must be of type
string or an instance of Buffer, > TypedArray, or DataView. Received
an instance of Promise

This exception is caught by the try/catch, and the file is never written.

Worse, when formatting files that are not supported by prettier (ex: yarn.lock), .format(...) fails and the promise rejection isn't handled, which lead to the following exception:

UndefinedParserError: No parser could be inferred for file "..."

and Node terminates the process, which is probably the cause of #3788 and #3773

Motivation and Context

This fixes file formatting and overall crashes during lerna version.

How Has This Been Tested?

Tested when doing a release in a project that uses lerna 7.1.4 and prettier 3.0.0

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Chore (change that has absolutely no effect on users)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[fahslaj]

Thank you @BenoitZugmeyer !