change CI ref

variables:

  # note: GitLab cannot reference variables defined by users in the include ref:, we need to use a YAML anchor for this

  # see https://docs.gitlab.com/ci/yaml/includes/#use-variables-with-include for more information

  IVAS_CODEC_CI_REF: &IVAS_CODEC_CI_REF main

  IVAS_CODEC_CI_REF: &IVAS_CODEC_CI_REF unify-complexity-measurements

  # If you need to set some config variable only in a local branch, then add an overwrite here

  # One example is DISABLE_HRTF - this will be set on a branch which is about to be merged and will be removed in a subsequent second MR

  # this is more easily done directly here in the child repo