PHP 8.4 support, fix psalm notices

[batyrmastyr]

Q	A
Is bugfix?	✔️support for DNF types, PHP 8.4 deprecations
New feature?	❌
Breaks BC?	❌
Fixed issues	—

Fixed PHP 8.4 deprecation warnings and psalm tests.

Updating CI to check PHP 8.4, fixing backward compatibility test - in another PR.

[codecov]

Codecov Report

Attention: Patch coverage is 92.30769% with 1 line in your changes missing coverage. Please review.

Project coverage is 95.72%. Comparing base (7b47b39) to head (b72e905).
Report is 6 commits behind head on master.

Files with missing lines	Patch %	Lines
src/ClassConfigFactory.php	90.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master      #75      +/-   ##
============================================
- Coverage     96.62%   95.72%   -0.90%     
- Complexity       99      101       +2     
============================================
  Files            10       10              
  Lines           296      304       +8     
============================================
+ Hits            286      291       +5     
- Misses           10       13       +3     

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[vjik]

• Add all supported PHP versions to CI
• Change PHP constraint in composer.json to 8.0 - 8.4