refactor: Including catalog as a part of Modulith module apiml

[pj892031]

Description

This PR is based on a branch that collects all PRs required to add the API Catalog into the apiml module.

Linked to # (issue)
Part of the # (epic)

List of tasks

• Removal of unused code (refactor: Removal of using eureka endoints and asynchronous caching #4187)
  • Loading asynchronously with caches
  • Usage of HTTP to download the Eureka registry
  • Event management (based on direct loading from Eureka)
  • Standalone mode
• Update base branch of this PR (once it is possible)
• Obtaining swagger from another module without a REST call (valid for GW, CS)
  • org.springdoc.api.AbstractOpenApiResource#getOpenApi(java.lang.String, java.util.Locale)
• Change the controllers and the service to use WebFlux instead of servlets (refactor: Replace MVC by WebFLux in the API Catalog #4196)
  • Change security configuration
  • Change configuration (remove the servlet parts)
• Move the service to be a part of Modulith
  • Add dependencies to the apiml module
  • Register the API Catalog statically (+ removal of onboarding)
  • Update IT
    • Checking if the APIML is up
    • Configuration of GA
    • To be part of testci-modulith
    • Run E2E twice (microservices + modulith)
  • Use the same basecode as other services (The API Catalog does not use the same code base #4183)
• Replace ImageController with static source configuration
• Replace usage of EurekaClient by DiscoveryClient (refactor: Replacement EurekaClient by DiscoveryClient #4203)
• Allow disabling the service
• Prefer instances on the same system (see finding first instanceInfo - sort by hostname and port before - first to prefer the same)
• GatewayInstanceInitializer removal? (maybe part of a different story)
• ? Define @Cacheable to speed up endpoints ?
• RSE API swagger parsing error in API ML #3910 (comment)
• Clean up (review of the whole branch)
• Remove branch reboot/catalog-modulith from the list of GA for PR (https://github.com/zowe/api-layer/pull/4187/files#diff-4761c5069b46ce96f49d74476da61f43ced3abc73d22254cd95a2be0e250a593)
• Removal of documentation about removed features of the API Catalog (standalone mode)

Type of change

• refactor: Refactor the code

[pablocarle]

The base in this PR should be v3.x.x