[#2788] zero-initialize digest buffer in rsAuthCheck
[#2788] zero-initialize digest buffer in rsAuthCheck

janiheikkinen/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,PaulVanSchayck/irods,janiheikkinen/irods,janiheikkinen/irods,janiheikkinen/irods,janiheikkinen/irods,janiheikkinen/irods,PaulVanSchayck/irods,janiheikkinen/irods,janiheikkinen/irods,janiheikkinen/irods,PaulVanSchayck/irods