This introduces ember-a11y-testing to acceptance tests via a helper
wrapper that allows us to globally ignore rules that we can address
separately. It also adds fixes for the aXe rules that were failing.
This includes fixes for newer template lint rules that came along with
updating that dependency, which was necessary to be able to use
the no-curly-component-invocation rule. It also updates some curly
invocations that I missed in #8075.
This is mostly a direct application of the ember-angle-brackets-codemod.
I manually restored newlines in multi-line component invocations, usually
preserving file line length except for now-non-positional link-to @route.
I needed to rename task to taskState in some cases to avoid Ember
Concurrency naming conflicts.
