Ugly line splitting for 3.10+ union type hints

[NiklasRosenstein]

Describe the bug

I've run across an issue where the following code gets formatted not very nicely. This particular snippet should IMO already satisfy Black with line_length=120.

def main(
    client: AppRole,
    role_name: str = Option(..., help="The name of the role to generate a secret ID for", metavar="ROLE_NAME"),
    secret_id: str | None = Option(
        None,
        help="A custom secret ID to use. If not specified, one will be generated.",
        metavar="SECRET_ID",
    ),
    metadata: str | None = Option(None, help="JSON-formatted metadata to associate with the secret ID", metavar="JSON"),
    metadata_file: Path | None = Option(
        None,
        help="A file containing JSON-formatted metadata to associate with the secret ID",
    ),
) -> None:
    """Generate a new secret ID for an approle."""

But running Black 23.3.0 over it gives an ugly split before two of the three | None parts:

def main(
    client: AppRole,
    role_name: str = Option(..., help="The name of the role to generate a secret ID for", metavar="ROLE_NAME"),
    secret_id: str
    | None = Option(
        None,
        help="A custom secret ID to use. If not specified, one will be generated.",
        metavar="SECRET_ID",
    ),
    metadata: str | None = Option(None, help="JSON-formatted metadata to associate with the secret ID", metavar="JSON"),
    metadata_file: Path
    | None = Option(
        None,
        help="A file containing JSON-formatted metadata to associate with the secret ID",
    ),
) -> None:
    """Generate a new secret ID for an approle."""

To Reproduce

Run black example.py --line-length 120 on the above snippet.

Expected behavior

Black should not split str | None before the |. There appears to be no reason to do so as the line is not too long.

Environment

• Black's version: 22.3.0
• OS and Python version: Python 3.8.10

Additional context

[yilei]

This is a duplicate of #2316