[7.1] 8.2.3.1. Qualifiers - add information about @Any qualifier

Documentation: https://access.stage.redhat.com/documentation/en/red-hat-jboss-enterprise-application-platform//7.0/development-guide/chapter-8-contexts-and-dependency-injection-cdi

Issue:
Within the doc, there are several usages of @Any qualifier but it is never explained. It is a very common occurrence in CDI and I think it is worth mentioning.

Suggested solution:
Within the section 8.2.3.1. Qualifiers we can add a subsection or maybe just two/three lines which will mention this. As a reference to what @Any actually is/does, see CDI spec.
All the mentions of @Any appear after section 8.2.3.1 therefore no more changes would be necessary.