bug#56467: vala command compiles files instead of running them

[two]

the bin/vala-0.54 shell script executes bin/valac-0.54 which executes 
bin/.valac-0.54-real.
it should execute bin/.vala-0.54-real instead.

expected (was the case before guix's update):
$ vala hello.vala
Hello, World!
$ ls
hello.vala

actual:
$ vala hello.vala
$ ls 
hello hello.vala
$ ./hello
Hello, World!