[CS Fix] Consistent coding-style of concatenation operator usage
[Fix CS] Unneeded whitespace around negation operator
merged branch canni/fix_cs (PR #7546)

This PR was merged into the master branch.

Discussion
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[Fix CS] Fix whitespace around concatenation operator

| Q             | A
| ------------- | ---
| Fixed tickets | n/a
| License       | MIT

Commits
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553e294 [Fix CS] Unneeded whitespace around negation operator
7c47e34 [CS Fix] Consistent coding-style of concatenation operator usage
[HttpFoundation][Session] Better detection of existing sessions.

Extended and improved tests, and introduced a way to work with applications
that start the PHP session using session_start()