This PR was merged into the 6.0 branch.Discussion----------[Messenger] remove legacy code paths| Q             | A| ------------- | ---| Branch?       | 6.0| Bug fix?      | no| New feature?  | no| Deprecations? | no| Tickets       | -| License       | MIT| Doc PR        | -Should make tests green. (and missed in#41319)Commits-------6d65673 [Messenger] remove legacy code paths

This PR was squashed before being merged into the 5.2 branch.Discussion----------[Messenger] Fixed BC layer for RedeliveryStamp| Q             | A| ------------- | ---| Branch?       | 5.2| Bug fix?      | no| New feature?  | no| Deprecations? | yes| Tickets       | Related to#41319 (comment)| License       | MIT| Doc PR        | n/aIn Symfony 6, the second argument to RedeliveryStamp's constructor will be a DateTimeInterface. We should already allow people to instantiate this object with the Symfony 6 way.Commits-------ac3c4d7 [Messenger] Fixed BC layer for RedeliveryStamp

…t` config option (andrew-demb)This PR was merged into the 6.0 branch.Discussion----------[Messenger] Remove mention to unsupported `prefetch_count` config option<!--If your pull request fixes a BUG, use the oldest maintained branch that containsthe bug (seehttps://symfony.com/releases for the list of maintained branches).If your pull request documents a NEW FEATURE, use the same Symfony branch wherethe feature was introduced (and `6.x` for features of unreleased versions).-->`prefetch_count` was removed insymfony/symfony#41319Commits-------b8602c4 Remove mention to unsupported `prefetch_count` config option