[BUGFIX beta] Deprecate outlet TemplateFactory support

[chancancode]

Backport of #20577

The exact code itself will probably apply cleanly to LTS as well. Logistically I'm not sure if we need to bother. We probably want to release emberjs/ember-test-helpers#1445 before merging this into the next beta, so people have something to upgrade to.

[chancancode]

Fix is merged upstream, pending release

[chancancode]

Upstream fix has been released in @ember/test-helpers v3.2.1, I re-ran the failing ember-try scenario locally on embroider-css-modules (where @ijlee2 first noticed and reported the problem) and confirmed that 1) it passes with deprecation on canary 2) it passes with no deprecations with the latest @ember/test-helpers. So I think we are good to go.

@kategengler do I update the available/enabled field on canary after this goes out with beta?

[ijlee2]

Upstream fix has been released in @ember/test-helpers v3.2.1, I re-ran the failing ember-try scenario locally on embroider-css-modules (where @ijlee2 first noticed and reported the problem) and confirmed that 1) it passes with deprecation on canary 2) it passes with no deprecations with the latest @ember/test-helpers. So I think we are good to go.

@kategengler do I update the available/enabled field on canary after this goes out with beta?

@chancancode Thanks for looking into the issue and releasing a patch for @ember/test-helpers.

In ijlee2/embroider-css-modules#120, I confirmed that updating @ember/test-helpers to v3.2.1 allows me to remove the ember-try configuration allowedToFail: true for ember-canary scenarios.

https://github.com/ijlee2/embroider-css-modules/actions/runs/6926965437/job/18839976721