Object with @Pattern is misinterpreted into 'Try it out' view

Q&A (please complete the following information)

• OS: Ubuntu 20.04 and Windows 10
• Browser: Chrome
• Version: 100.0.4896.127 (64 bit)
• Method of installation: Maven/WebJar via springdoc-openapi
• Swagger-UI version: v4.10.3
• Swagger/OpenAPI version: OpenAPI 3.0

Content & configuration

Bug is reproducible using an api object with bean-validation @Pattern annotation. If none example attribute is specified into @Schema annotation, Swagger-UI will render a huge value into that api object param (inside 'Parameters' tab of Try it out view).

This unexpected behaviour may exist from v4.6.2. PR: #7829

It's not being taking into account that example field can be null and Swagger-ui is trying to conform "string" type to the regex pattern.

Example Swagger/OpenAPI definition:

openapi: 3.0.1
info:
  title: OpenAPI definition
  version: v0
servers:
  - url: http://localhost:8080
    description: Generated server url
paths:
  /api/demo:
    get:
      tags:
        - demo-controller
      operationId: retrieveDemo
      parameters:
        - name: input
          in: query
          required: true
          schema:
            $ref: '#/components/schemas/DemoBean'
      responses:
        '200':
          description: OK
          content:
            '*/*':
              schema:
                $ref: '#/components/schemas/DemoBean'
components:
  schemas:
    DemoBean:
      type: object
      properties:
        Demo Name:
          type: string
          description: Demo Name field example
        Demo Email:
          pattern: ^[_A-Za-z0-9-\+]+(\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\.[A-Za-z0-9]+)*(\.[A-Za-z]{2,})$
          type: string
          description: Demo Email with bean-validation and example value
          example: valid@email.com
        Demo email confirm:
          pattern: ^[_A-Za-z0-9-\+]+(\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\.[A-Za-z0-9]+)*(\.[A-Za-z]{2,})$
          type: string
          description: Demo email confirm with bean-validation and non example value

To reproduce...

Steps to reproduce the behavior:
Check it out this demo project https://github.com/GandalfTheBlack16/demo-swagger

Expected behavior

Field 'demo email confirm' value to be "string"

Screenshots

Reproduce the issue with the supplied OpenAPI definition, comparing the Try it out Parameters view for fields with and without an example. Start at the rendering path for object query parameters and pattern-constrained strings, using the linked demo project and PR #7829 as context. Done means the field without an example displays "string" while the field with an example remains unchanged.