fix(content-gate): support zero paragraph excerpt

[miguelpeixe]

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Changes proposed in this Pull Request:

NPPM-2531

Support setting visible paragraphs to zero when configuring the content gate. This means no content should render, and the gate should display immediately.

How to test the changes in this Pull Request:

1. Make sure you have Woo Memberships and content gate configured
2. While on release, navigate to Audience -> Configuration -> Content Gating, and edit your gate
3. Set the gate's "visible paragraphs" to zero
4. Visit a gated article and confirm the first paragraph renders
5. Checkout this branch, refresh, and confirm the gate renders without any content

Other information:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes, as applicable?
• Have you successfully ran tests with your changes locally?

[leogermani]

Will this play (and merge) nicely with #4394 ?

[miguelpeixe]

Yes, but I'll have to move the new file (from #4370). Should be fine.

[chickenn00dle]

This works as expected so I'll approve.

I did have one small non-blocking issue with the appearance of the gate with no excerpt. The ellipses above the gate content seems redundant without any excerpt above it. Do we need it? Or do we need some other type of transition from post header to gate content?

[miguelpeixe]

Thanks for the review, @chickenn00dle!

The ellipses above the gate content seems redundant without any excerpt above it.

That's part of the gate content. The editor can remove it if running the gate without any starting content. It's also the case if they configure an overlay gate.

[matticbot]

🎉 This PR is included in version 6.29.1 🎉

The release is available on GitHub release

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