fix recaptcha race condition

[WeidiDeng]

Description
Currently when using recaptcha, there's a chance when vue mounted was called, render was not ready. Can be reproduced on macos big sur 11.01 and ipad OS 14.2 safari browser.

Using ready function to render the recaptcha. Fixes 1167;

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Further comments
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❤️ Thank you!

[o1egl]

Well done!