IBX-8470: Upgraded codebase to Symfony 6

[alongosz]

Caution

This is a part of bigger set of changes, to be merged together when ready

• ❗ Remove TMP commits before merge ❗

🎫 Issue	IBX-8470

Related PRs:

• IBX-8470: Upgraded codebase to Symfony 6 core#447
• IBX-8470: Bumped Symfony to version 6 doctrine-schema#27
• IBX-8470: Upgraded codebase to Symfony 6 test-core#13

Description:

This PR bumps Symfony to v6 with necessary codebase upgrades.

Please take a look at RestAuthenticator changes. getPassword method is completely gone from UserInterface, without any replacement, so not sure what will be end result of that change. Temporarily placed empty string there.

I'll need to go back to REST Functional tests once full-stack app is upgraded.

Key changes:

• [Composer] Dropped obsolete ci-scripts from dev requirements
• Bumped Symfony packages requirements to ^6.4
• Dropped Symfony Container dependency from REST base controller
• Dropped Symfony Container dependency from Content controller
• [Security] Aligned RestAuthenticator with Symfony 6
• Improved Controllers code quality
• Aligned SessionController with Symfony 6
• [PHPStan] Removed resolved issues from the baseline
• [Tests] Aligned VisitorTest with Symfony 6

QA:

Sanities in the form of regression tests.

Documentation:

No documentation required.

[sonarcloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud