Watch 5.3.x branch in the CI pipeline
Watch 5.3.x branch in the CI pipeline

Main branch has moved to the 6.0.x line, so this commit updates this CI
pipeline to the new 5.3.x maintenance branch.

spring-projects/spring-framework,spring-projects/spring-framework,spring-projects/spring-framework,spring-projects/spring-framework,spring-projects/spring-framework,spring-projects/spring-framework,spring-projects/spring-framework