MultiSchemaField does not pass formContext into type selector field

[skyboyer]

Prerequisites

• I have read the documentation;
• In the case of a bug report, I understand that providing a SSCCE example is tremendously useful to the maintainers.
• Ideally, I'm providing a sample Codesandbox demonstrating the issue.

Description

Suppose we have custom SelectWidget registered and it relies on formContext passed in. MultiSchemaField renders current SelectWidget to allow switching between types. But it never passes formContext in.

Steps to Reproduce

1. Have a SelectWidget implementation that expects formContext to be in props
2. Register it as a SelectWidget through widgets props for Form.
3. Add anyOf or oneOf to the schema.

Expected behavior

SelectWidget gets proper props.formContext

Actual behavior

props.formContext is undefined.

Version

@rjsf/core 2.5.0

[heath-freenome]

Fixed in v5 beta via #3040, see the 5.x migration guide