Pull ReCaptcha library via Composer

[Gold]

A wishlist item for tracking the modernisation of how we manage third party libraries.

We need to remove third party libraries from our codebase and have them included via composer.

The 'make initcomposer' target will need to install the new libraries as well.

https://wiki.mahara.org/wiki/Proposals/Management_of_third_party_libraries

[Mahara Bot (dev-mahara)]

Patch for "main" branch: https://reviews.mahara.org/c/mahara/+/12720

[Mahara Bot (dev-mahara)]

Reviewed: https://reviews.mahara.org/c/mahara/+/12720
Committed: https://git.mahara.org/mahara/mahara/commit/d16ca8801fa7a271e939ef775afd088aa17f2ccd
Submitter: "Gold <email address hidden>"
Branch: main

commit d16ca8801fa7a271e939ef775afd088aa17f2ccd
Author: Gold <email address hidden>
Date: Fri May 6 11:28:26 2022 +1200

Bug 1971898: Pull libraries via Composer

This initial test removes the recaptcha library, adds this to the
composer.json, installs it via make init composer, adds a behat test for
it, and adds sanity checks to init.php to check for the new vendor
directory.

To test, install a clean site and point a browser at it.

I've added cwegans/composer-patches and a patch on recaptcha that
removes the examples and tests dir.

Configure the site to use recaptcha under Site options > Security.
Enable on the registration and contact forms and insert the site and
secret keys.

For full testing you will want to create test keys for your
development environment at https://www.google.com/recaptcha/

For minimal testing (verifying that the library is loading and for
testing with behat) you can use the public test keys here:
https://developers.google.com/recaptcha/docs/faq#id-like-to-run-automated-tests-with-recaptcha.-what-should-i-do

While logged out browse to the Register and Contact pages.

Change-Id: I44b5669781b0c5ea6a85d5fbdb2c3e0617be4099