tests: Check refspec switch updates git branch/commit correctly

Mercurial has no concept of a local tracking branch so we only need to
test git repositories here.

Signed-off-by: Paul Barker <pbarker@konsulko.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

tests/test_refspec/oe-init-build-env

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+true