Implement Form Interface to Add reCaptcha validation modal [#3453892]

Problem/Motivation

We're getting tremendous amount spam accounts via social_auth. To prevent bots, suggesting to implement form interface and adding captcha points instead of exposing routes directly.

Note: PR will include `use-ajax`. Currently recaptcha module is not working with jquery ui modals without https://www.drupal.org/project/recaptcha/issues/2493183 patch.
Note: This PR https://www.drupal.org/project/social_auth/issues/3453885 must be used before applying this.

Issue fork social_auth_google-3453892

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ISSUE-3453892-3.0.0 changes, plain diff MR !8
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