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

Signal-Desktop: update to 6.19.0.
https://github.com/void-linux/void-packages/pull/44074

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

#### Local build testing
- I built this PR locally for my native architecture, x86_64

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This uses a hacky `vsed` command to build with our version of node (16.19.0). It works for me, but it'd be much better if #41239 was merged soon.