Add IPv6 info dialog

[raksooo]

This PR adds an info dialog to the "Enable IPv6" feature and removes the now redundant footer text.

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This change is 

[linear]

DES-212 Add information dialog to "Enable IPv6" feature

Add information ℹ️ dialog to the Enable IPv6 setting in the desktop GUI. Richard says that many users don't understand what it does and if they need it. The truth is that most people don't need this, and if a user don't know what it does, they most likely don't need it.

Text inside dialog:

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When this feature is enabled, IPv6 can be used alongside IPv4 in the VPN tunnel to communicate with internet services.

IPv4 is always enabled and the majority of websites and applications use this protocol. We do not recommend enabling IPv6 unless you know you need it.

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Zeplin: https://zpl.io/Z0GDlnJ

[MarkusPettersson98]

Reviewed 1 of 1 files at r1, 1 of 1 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved