using relative path does help a lot

Signed-off-by: Joerg Jaspert <joerg@debian.org>

diff --git a/scripts/backports/expire_dumps b/scripts/backports/expire_dumps
index 02095f6fad039636b6756bb07a01e81346ae9f38..649cd12a63496ed5ac122bc033c43f5f3e64fed9 120000 (symlink)
--- a/scripts/backports/expire_dumps
+++ b/scripts/backports/expire_dumps
@@ -1 +1 @@
-/develop/vcs/dak/dak/scripts/debian/expire_dumps
\ No newline at end of file
+../debian/expire_dumps
\ No newline at end of file