Potentially vendor some unmaintained servo-specific bluetooth crates

[arihant2math]

https://github.com/akosthekiss/blurmac is pretty servo-specific and also unmaintained, but we vendor it in the third_party directory and keep it somewhat up to date. This originally stems from when servo/devices was folded into servo/servo. I think we should do the same for https://github.com/szeged/blurz and https://github.com/szeged/blurdroid given that they are also unmaintained and could use some updates.

[mrobinson]

I think it might make more sense to switch Servo to use btleplug (or a similar crate) or perhaps remove the Bluetooth feature entirely since it's unmaintained.

[arihant2math]

I might take a shot at modernizing it; I'll look into btleplug.

[arihant2math]

See also: #40142

[arihant2math]

btleplug is async though, means the bluetooth crate might need access to the runtime if we go down that route.