Fixed broken unit tests that use _version

- _verstion now outputs the short git sha1 id and not longer the
  task version when building from the git repository.

test/hook.post-start.t

@@ -52,7 +52,7 @@ if ($output =~ /PUC-Rio/)
 {
   # Test the hook.
   $output = qx{../src/task rc:hook.rc _version};
-  like ($output, qr/^marker.+\n\d\.\d+\.\d+/ms, 'Found marker before output');
+  like ($output, qr/^marker.+\n\w{7}/ms, 'Found marker before output');
 }
 else
 {

test/hook.pre-exit.t

@@ -53,7 +53,7 @@ if ($output =~ /PUC-Rio/)
 {
   # Test the hook.
   $output = qx{../src/task rc:hook.rc _version};
-  like ($output, qr/\n\d\.\d+\.\d+/ms, 'Found marker after output');
+  like ($output, qr/\n\w{7}/ms, 'Found marker after output');
 }
 else
 {