Add bash completion for `--context`

Signed-off-by: Harald Albers <[email protected]>

contrib/completion/bash/docker-compose

@@ -603,6 +603,7 @@ _docker_compose() {
 		--tlsverify
 	"
 	local daemon_options_with_args="
+		--context -c
 		--env-file
 		--file -f
 		--host -H