wiki sidebar in o3de and other related repositories needs a cohesive sidebar section for test tools documents

[smurly]

Test tool documentation that covers testing tools and practices are being added to various repository wiki pages. a sidebar linking group needs to be created to offer navigation to these documents
a new document was added for multi-test framework, but other than direct linking there is no sidebar discoverable link for it.

https://github.com/o3de/o3de/wiki/Multitest-Framework-(Running-multiple-tests-in-one-executable)

we need to create a section in the wiki sidebar to house links to this and future documents
https://github.com/o3de/o3de/wiki/_Sidebar/_edit

not certain what to name this section. possibly Test Practices and Tooling

[Kadino]

Good to add a section, and recommend it prominently link to primary documentation at https://www.o3de.org/docs/user-guide/testing/

It would be nice like to avoiding the "many different places for documentation" sprawl, where possible.

[Kadino]

Could be good to add a "Getting Started" wiki page which has links, which include to the o3de.org site and this sig-testing repo.