gsi-pubsign-release.sh follows symbolic link

Use `find -L` and `cp --dereference` to follow symlinks.

Bug: 149803895
Test: manual
Merged-In: Ide2ae854dd61e595ca2676634f660241343e6dba
Change-Id: Ide2ae854dd61e595ca2676634f660241343e6dba
(cherry picked from commit abdcbb3f8381b5bc5c198ea23778ce4a409932b8)
1 file changed