Plugins CheckPropTypes Failes for swagger-ui-react

Q&A (please complete the following information)

• OS: macOS
• Browser: chrome
• Version:
• Method of installation: yarn
• Swagger-UI version: 3.35
• Swagger/OpenAPI version: OpenAPI 3.0

Content & configuration

Example Swagger/OpenAPI definition:

# your YAML here

Swagger-UI configuration options:

        <SwaggerUI
          url="/api/v2/openapi.yaml"
          plugins={[sidebarPlugin]}
		/>

export default function sidebarPlugin(system: any): sidebarPluginInterface {
  return {
    wrapComponents: {
      operations: (Original, system) => (props) => {
		}
	}
  }
}

Describe the bug you're encountering

The following warning/error shows in dev environment.
```Warning: Failed prop type: Invalid prop plugins[0] of type `function` supplied to `SwaggerUI`, expected `object`.

I think the PropTypes definition for plugins on the swagger-ui-react package is incorrect.

### To reproduce...

Steps to reproduce the behavior:
1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

### Expected behavior
<!-- A clear and concise description of what you expected to happen. -->

### Screenshots
<!-- If applicable, add screenshots to help explain your problem. -->

### Additional context or thoughts
<!-- Add any other context about the problem here. -->

Start by reproducing the warning with the shown swagger-ui-react configuration and function-valued sidebarPlugin. Then inspect the swagger-ui-react package's PropTypes definition for the plugins prop; done means the supplied plugin no longer triggers the reported invalid-prop warning.