[HttpFoundation] Add accessors methods to session handlers
merged branch dosten/ticket_7683 (PR #8303)

This PR was squashed before being merged into the master branch (closes #8303).

Discussion
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[HttpFoundation] Add accessors methods to session handlers

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #7683
| License       | MIT
| Doc PR        |

Commits
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460c696 [HttpFoundation] Add accessors methods to session handlers