Fix incorrect reference to vscoq.trace.server

[cpitclaudel]

The README and the settings say to use vscoq.trace.server, but AFAICT this setting does nothing. Looking at the code:

vscoq/client/src/client.ts

Lines 23 to 28 in 26f3f1f

	super(
	'vscoq-language-server',
	'Coq Language Server',
	serverOptions,
	clientOptions
	);

… it appears that the right name is vscoq-language-server, not vscoq. Indeed, with that setting set, I do get a trace (and I don't with the normal one).

An alternative fix would be to change the snippet above to have vscoq instead of vscoq-language-server. Not sure what the consequences would be.

[rtetley]

Thanks ! Took the liberty of rebasing, will merge once CI passes !