liboqs: fix missing symbolic link installation

liboqs: fix missing symbolic link installation

The current installation process fails to correctly install the
'liboqs.so' symbolic link due to an incorrect path syntax (extra dot).

This prevents other packages from linking against liboqs
(e.g., using -loqs) during development, which was discovered while
testing PQC key exchange implementations dependent on OQS.

Removes the trailing dot to ensure the symbolic link is preserved and
copied correctly to the destination directory.

Signed-off-by: Ho Kim <redacted>