Add "learn more" links to panels

[JohnPixle]

@lushkant I noticed that several of our panels are missing the "Learn More..." link that directs the users to our documentation.

❇️ In the screenshot references I accidentally wrote "Read More", but let's use "Learn more" instead.

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• [x] Deactivate SK panels should point to: https://analogwp.com/docs/selectively-deactivate-disable-style-kit-panels/

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• [x] User roles should point to: https://analogwp.com/docs/user-roles-and-style-kits-visibility/

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• [x] bg color classes https://analogwp.com/docs/background-color-classes/

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• [x] Elementor forms

https://analogwp.com/docs/elementor-forms/

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• [x] Shadows https://analogwp.com/docs/global-shadows/

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Let me know if you need any clarifications or if you have any other suggestions!

[JohnPixle]

@lushkant the Learn more link seems to be missing from the user roles panel.