REF reCAPTCHA Simplify buildCustom function on Registration form

[mattwire]

Overview

This is a refactor in preparation for moving the reCAPTCHA code to the new reCAPTCHA extension for the event registration pages.
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

Split into 3 commits for ease of review.

1. Typos in comments and unused code lines.
2. Simplify the buildCustom function (use ?w=1 in URL to see that this is only removing the if that wraps everything in the function, switching to CRM_Core_Session::getLoggedInContactID(); and moving the $button to nearer the only place it is used.
3. $viewOnly parameter is never used in this function (looks like a copy/paste from other code that left it in place).

Comments

[civibot]

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[eileenmcnaughton]

I did a trawl & didn't find any evidence that viewOnly is passed in so I agree with cleaning it up

[mattwire]

Thankyou @eileenmcnaughton