Add 2 new subscribe patterns

[thomasguillot]

All Submissions:

• Have you followed the Newspack Contributing guideline?
• Does your code follow the WordPress' coding standards and VIP Go coding standards?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changes proposed in this Pull Request:

This PR adds 2 new subscribe patterns, including one without any image.

These 2 patterns are based on Hechinger Report (except here I'm using Jetpack Mailchimp). E.g. https://hechingerreport.org/desperate-parents-need-help-as-coronavirus-upends-our-lives/

How to test the changes in this Pull Request:

1. Switch to this branch
2. Edit a page/post/popup. Do you see the new patterns?
3. Try to add them to your page/post/popup.

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?

[jeffersonrabb]

Looks good.

[matticbot]

🎉 This PR is included in version 1.3.0 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀