Ensure spring-test builds against HttpComponents 4.5
Ensure spring-test builds against HttpComponents 4.5

This is necessary to ensure that the version of HtmlUnit that we use is
compatible with HttpComponents 4.5.

Issue: SPR-13158

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