…ate` (#11417)

While testing the collator protocol revamp on westend I noticed
"Inconsistency while adding a leaf to the `ClaimQueueState`. Expected on
session change." pops up a lot at regular intervals.

Long story short, when writing this code I assumed that the CQ never
change but from a `ClaimQueueState` point of view this is not true. ~~On
session change the validators in the active set are reshuffled and end
up in different backing groups.~~ ON group rotation the validators are
assigned on a new core. In this case we start fetching the claim queue
for the newly assigned core and the future assignments in
`ClaimQueueState` are no longer valid so overwriting them is the right
thing to do.

We could also implement a logic which detects assignment change,
notifies the claim queue and cleans it up but it's an additional
complexity which doesn't add any benefits.

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Co-authored-by: cmd[bot] <41898282+github-actions[bot]@users.noreply.github.com>
(cherry picked from commit 4afd7bd)