Merge branch 'update/update_branch_version_to_2_5_7' into 'Support/2.5.X'

update version number and changelog

See merge request !556
1 job for 2.5.7
latest
Status Name Job ID Coverage
  Tests
failed unit-tests:php-7.2 #25031

 
Name Stage Failure
failed
unit-tests:php-7.2 Tests There has been a timeout failure or the job got stuck. Check your timeout limits or try again
No job log