Add Wordfence Intelligence CE as an API provider

[iamdharmesh]

Description of the Change

PR adds support for Wordfence API to check reported vulnerabilities for WordPress core, installed plugins and themes.

Users can choose Wordfence API for vulnerabilities scan by adding the VULN_API_PROVIDER constant in wp-config.php

define( 'VULN_API_PROVIDER', 'wordfence' );

Apart from Wordfence Intelligence CE support, PR makes the below changes.

• Fixed PHPCS errors
• Added workflow for PHPCS
• Added Build release zip workflow (to attach the zip to release and manually trigger build zip)
• Added Stable build workflow to update the stable branch with built code on push to the trunk branch.
• Divided tests for each API provider as a separate check

Closes #76

How to test the Change

1. Add a VULN_API_PROVIDER constant in wp-config.php as below.

   define( 'VULN_API_PROVIDER', 'wordfence' );

2. Try the given vuln commands in readme to scan for vulnerabilities.
3. Make sure all commands are working fine.
4. Regression: Make sure all commands are working fine with other services (WPScan and Patchstack)

Changelog Entry

Added - Wordfence Intelligence CE as an API provider.

Credits

Props @iamdharmesh @jeffpaul Charles Sweethill, Matt Barry (Wordfence Team)

Checklist:

• [x] I agree to follow this project's Code of Conduct.
• [x] I have updated the documentation accordingly.
• [x] I have added tests to cover my change.
• [ ] All new and existing tests pass.

[iamdharmesh]

Note: Functional tests for WPScan failing due to exceeding the Daily API limit.

[jeffpaul]

@iamdharmesh heads up on https://www.wordfence.com/intelligence-documentation/v2-accessing-and-consuming-the-vulnerability-data-feed/#changes, might require a tweak here before merge/release?

[iamdharmesh]

@iamdharmesh heads up on wordfence.com/intelligence-documentation/v2-accessing-and-consuming-the-vulnerability-data-feed/#changes, might require a tweak here before merge/release?

@jeffpaul We are not using the copyright field, So, our implementation will not affect by this.

[jeffpaul]

Note that I'm coordinating with the folks at Wordfence for a code review here as well, so let's hold before merging to give them a chance to provide input as well.

[iamdharmesh]

Update:

@jeffpaul I have made changes related to JSON parser here and I will work on other changes like adding the references column, renaming the fix column to Fixed in, adding show API provider information etc... next week.

[jeffpaul]

@iamdharmesh probably good to merge here and continue with the remainder of the 1.2.0 issues