gitlab-ci : Package ‘mysql-client’ has no installation candidate

I am using “mysql 5.7” in my “gitlab-ci” file and use “apt-get -y install mysql-client” to install sql client but it is always giving me error. ERROR : “Package mysql-client is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source”. Thanks in advance…