Fix changelog, react-bootstrap README (rjsf-team#4278)

Author: nickgros

CHANGELOG_v6.md

@@ -33,37 +33,3 @@ should change the heading of the (upcoming) version to include a major version b
 - IconButton: Remove deprecated `block` prop
 - RangeWidget: Use `FormRange` component
 - SelectWidget: Use new FormSelect component, remove `bsPrefix` prop to achieve correct styling
-
-# 5.15.1
-
-## @rjsf/core
-
-- fix `getFieldNames`. Now correctly defines an array of primitives.
-
-## @rjsf/validator-ajv6
-
-- Updated the `AJV6Validator` class to expose the internal `ajv` object, allowing access to support a fix related to [#3972](https://github.com/rjsf-team/react-jsonschema-form/issues/3972)
-
-## @rjsf/validator-ajv8
-
-- Updated the `AJV8Validator` class to expose the internal `ajv` object, allowing access to support a fix related to [#3972](https://github.com/rjsf-team/react-jsonschema-form/issues/3972)
-
-## Dev / docs / playground
-
-- Updated the documentation to describe how to use the newly exposed `ajv` variable
-
-# 5.15.0
-
-## @rjsf/mui
-
-- fix gap in text and select widget outlines when `"ui:label": false` is specified.
-
-## @rjsf/utils
-
-- Updated `resolveAllReferences()` to use own recurse list for each object properties, fixing [#3961](https://github.com/rjsf-team/react-jsonschema-form/issues/3961)
-- Added an experimental flag `allOf` to `experimental_defaultFormStateBehavior` for populating defaults when using `allOf` schemas [#3969](https://github.com/rjsf-team/react-jsonschema-form/pull/3969)
-
-## Dev / playground
-
-- add missing typescript project reference for `utils` in `validator-ajv6` and `validator-ajv8` packages tsconfigs
-- Added a dropdown for changing the `experimental_defaultFormStateBehavior.allOf` behaviour in the playground