Add Volt to "Adoption" page

[notmandatory]

See logo and blub here:

https://github.com/orgs/bitcoindevkit/discussions/64#discussioncomment-9685092

[reez]

I'll do this and assign to myself-

[reez]

Added a PR for this-

[Zero-1729]

Thank you for doing this @reez in #199

[reez]

Thank you for doing this @reez in #199

No problem, thank you for the awesome app using BDK!

[reez]

Merged in #199 - closing