raise dependency on PHP 8.0

raise dependency to laminas-stdlib 3.10.1

raise dependency on PHP 7.4

keep compatibility using laminas-zendframework-bridge
  as this is only used using compat autolader
raise dependency to laminas-stdlib 3.6

switch to phpunit9

raise dependency to PHP 7.3
raise dependency to laminas-stdlib 3.2.1
raise dependency to laminas-zendframework-bridge 1.0.4
switch to phpunit8