Inconsistent casing of swagger-config causes fetch error

[vchen8761]

Describe the bug

• When the default ObjectMapper uses UpperCamelCase strategy, the URL list in Swagger config has inconsistent property naming, which leads to a fetch error in the swagger-ui

To Reproduce
Steps to reproduce the behavior:

• What version of spring-boot you are using? '2.5.4'
• What modules and versions of springdoc-openapi are you using? '1.5.10'
• Here is a reprex of the issue: https://github.com/vchen8761/springboot-demo

The issue needs to be reproduced with the following setups:

• Actuator endpoints use a different port, so there is a URL list in swagger-config (for multiple Swagger definitions).
• Default ObjectMapper of the SpringBoot project uses UpperCamelCase strategy other than default (lowerCamelCase or snake_case both work because the related field names are only 1-word long, i.e. url and name).

Expected behavior

• No fetch error and actuator endpoints are listed in swagger-ui.html

Screenshots

See the screenshot above. On the right the items in urls has field names like Url and Name instead of url and name.