Calendly: Removed look behinds in regexes

[pablinos]

Changes proposed in this Pull Request:

Look behinds aren't supported by Firefox, IE and some other browsers, which prevented the Calendly block from registering correctly.

This change replaces those regular expressions with ones that use groups to grab what is needed from the string.

Is this a new feature or does it add/remove features to an existing part of Jetpack?

This fixes a bug with the soon to be launched Calendly block

Testing instructions:

With a Jetpack site, activate the beta blocks and test that the different types of embed code can still be used with the Calendly block.

Optionally test it in another browser that doesn't support look behinds e.g. Firefox.

Proposed changelog entry for your changes:

• N/A

[matticbot]

Caution: This PR has changes that must be merged to WordPress.com
Hello pablinos! These changes need to be synced to WordPress.com - If you 're an a11n, please commandeer, review, and approve D37816-code before merging this PR. Thank you!

[jetpackbot]

Thank you for the great PR description!

When this PR is ready for review, please apply the [Status] Needs Review label. If you are an a11n, please have someone from your team review the code if possible. The Jetpack team will also review this PR and merge it to be included in the next Jetpack release.

Scheduled Jetpack release: January 23, 2020.
Scheduled code freeze: January 16, 2020

Generated by 🚫 dangerJS against 8d1c636

[pablinos]

Fixes #14376

[jeherve]

Tests appear to fail now:
https://travis-ci.org/Automattic/jetpack/jobs/638156137?utm_medium=notification&utm_source=github_status

jetpack/extensions/blocks/calendly/test/utils.js

Line 44 in 2c3dbd9

describe( 'getAttributesFromEmbedCode', () => {

[matticbot]

pablinos, Your synced wpcom patch D37816-code has been updated.

[pablinos]

Whoops! Thanks @jeherve. That should be fixed now.

[jeherve]

Let's give this a try. It seems to work on my end!