[HttpKernel] made the cache key generation configurable for the default HttpCache store
feature#9151 [HttpKernel] made the cache key generation configurable for the default HttpCache store (fabpot)

This PR was merged into the master branch.

Discussion
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[HttpKernel] made the cache key generation configurable for the default HttpCache store

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #9088
| License       | MIT
| Doc PR        | n/a

Commits
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780b77a [HttpKernel] made the cache key generation configurable for the default HttpCache store