Simplify reCAPTCHA on ContributionBase form

[mattwire]

Overview

This is a refactor in preparation for moving the reCAPTCHA code to the new reCAPTCHA extension for the campaign signature form.
See https://lab.civicrm.org/dev/core/-/issues/2571

Before

More complex code.

After

Simpler code, will be easier to review next step which actually moves the code that adds the reCAPTCHA.

Technical Details

• Use CRM_Utils_ReCAPTCHA::enableCaptchaOnForm directly in ContributionBase - this was left over from a previous older refactor.
• Remove warning about reCaptcha missing key from contribution page - this is the only place that implements this "check" for reCAPTCHA enabled but not configured. It does not seem necessary as it is not implemented elsewhere - we could implement a system status check in the extension once all the code is moved across to check the reCAPTCHA configuration if required - but it seems unnecessary as the reCAPTCHA element will not be displayed if not configured and that should be trigger enough to check the settings..

Comments

[civibot]

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[eileenmcnaughton]

OK - I agree that a system check makes more sense & that displaying this might not always be appropriate. The functionality seems trivial enough/ arguable enough that removing it to simplify follow on work seems OK to me