Add WP version checker.

[mi5t4n]

Description

Whenever a new version of the WP is released, we need to update the Tested up to information in the readme.txt.

Feature

1. Create a scheduled workflow which will check a the latest WP version with the Tested up to information in the readme.txt.
2. Create a issue on the repository suggesting that we need to update the Tested up to information.
3. Auto assign the issue to a developer.