Add completion to compilation-read-command

[Spyros Roum <spyros.roum@posteo.net>]

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Hello all,

Recently, I started using `M-x compile` more but as I was used to my 
shell suggesting past commands as I type (and tools like atuin), I was 
missing auto-complete a lot.
I managed to add this functionality by writing a simple function based 
on compilation-read-command that uses completing-read instead of 
read-shell-command.
Then I used advice-add to overwrite the 
original compilation-read-command with mine.

So far this works well, and as far as I can tell there is no good reason 
not to make compile auto-completing, it already has a history that you 
can navigate anyway.

With that said, this is the first time I write here and the first time 
I'm trying to contribute to emacs, so I'm not sure what the best way to 
go from here would be.
I think some decisions would need to be taken, for once I am not sure if 
it's acceptable to change the default and make it completing or if there 
should be an option for it.

Looking forward to your feedback, thanks

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