Add test for the new find program workaround for Windows

test cases/windows/9 find program/meson.build

@@ -0,0 +1,4 @@
+project('find program', 'c')
+
+prog = find_program('test-script')
+test('script', prog)

test cases/windows/9 find program/test-script

@@ -0,0 +1,3 @@
+#!/usr/bin/env python
+
+print('1')