[HttpFoundation] fixed issue with session_regenerate_id (closes #7380)
merged branch fabpot/session-regenerate-fix (PR #8270)

This PR was merged into the 2.2 branch.

Discussion
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[HttpFoundation] fixed issue with session_regenerate_id (closes #7380)

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #7380
| License       | MIT
| Doc PR        | n/a

Commits
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77f2aa8 [HttpFoundation] fixed issue with session_regenerate_id (closes #7380)