…alidator (fabpot)This PR was merged into the 4.2-dev branch.Discussion----------[Validator] Deprecate checkMX and checkHost on Email validator| Q             | A| ------------- | ---| Branch?       | master| Bug fix?      | no| New feature?  | no <!-- don't forget to update src/**/CHANGELOG.md files -->| BC breaks?    | no     <!-- seehttps://symfony.com/bc -->| Deprecations? | yes| Tests pass?   | yes    <!-- please add some, will be required by reviewers -->| Fixed tickets |fixes#27559fixes#28665| License       | MIT| Doc PR        | symfony/symfony-docs#... <!-- required for new features --><!--Write a short README entry for your feature/bugfix here (replace this comment block.)This will help people understand your PR and can be used as a start of the Doc PR.Additionally: - Bug fixes must be submitted against the lowest branch where they apply   (lowest branches are regularly merged to upper ones so they get the fixes too). - Features and deprecations must be submitted against the master branch.-->Commits-------c6009a0 [Validator] deprecate checkMX and checkHost on Email validator