There's a merged pull request on the void-packages repository

gnupg: adopt, update to 2.3.7.
https://github.com/void-linux/void-packages/pull/38021

Description:
## Test/Stable/LTS/Legacy?!

GnuPG has a few different development branches, and they do change their mind sometimes about what those are. They used to say this:

> We are pleased to announce the availability of a new GnuPG release:
> version 2.3.0.  This release marks the start of public testing releases
> eventually leading to a new stable version 2.4.

Source: https://lists.gnupg.org/pipermail/gnupg-announce/2021q2/000458.html

But with 2.3.3, they changed their mind:

> Three different series of GnuPG are actively maintained:
> 
> - Version 2.3 is the current stable version with a lot of new features
>   compared to 2.2.  This announcement is about the latest release of
>   this series.
> 
> - Version 2.2 is our LTS (long term support) version and guaranteed to
>   be maintained at least until the end of 2024.
>   See https://gnupg.org/download/index.html#end-of-life
> 
> - Version 1.4 is only maintained to allow decryption of very old data
>   which is, for security reasons, not anymore possible with other GnuPG
>   versions.

Source: https://lists.gnupg.org/pipermail/gnupg-announce/2021q4/000466.html

I'd say packaging stable instead of LTS is fine, and if someone really needs LTS then we should have a separate LTS package instead.

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#### Testing the changes
- I tested the changes in this PR: **briefly**

So, considering this is a bit of a bigger change I selected `briefly` here, but I did do quite a bit of testing on my machine, and I've not noticed any breakage yet. Encryption/decryption still works, I can still authenticate to servers via ssh, with the key residing on a yubikey being accessed through gnupg-agent, everything good.

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