copy table entry key/value in util_table_add_query_encoded
copy table entry key/value in util_table_add_query_encoded

- avoid refering after the source string is freed
- initialize data.encoded_params to NULL

Signed-off-by: Hans Zandbelt <ed0aee6a22215d4e183b63ab4a45da7fb897917a@zmartzone.eu>
pingidentity/mod_auth_openidc,pingidentity/mod_auth_openidc