Improve usage NotFoundException for cases with definitions

[vjik]

Q	A
Is bugfix?	❌
New feature?	❌
Breaks BC?	❌
Fixed issues	-

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (aeb0856) to head (9234ad9).

Additional details and impacted files

@@             Coverage Diff             @@
##              master      #356   +/-   ##
===========================================
  Coverage     100.00%   100.00%           
- Complexity       161       165    +4     
===========================================
  Files             11        11           
  Lines            466       479   +13     
===========================================
+ Hits             466       479   +13     

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[what-the-diff]

PR Summary

• Expanded Change Log
  The CHANGELOG.md file has been updated to include the recent enhancement, improving usage for NotFoundException for specified cases.

• Enhanced Error Handling
  The code dealing with exception handling in the get() method located in the src/Container.php file has been refined. This involved the introduction of a new class NotFoundException within src/NotFoundException.php.

• Updated Test Assertions
  The message in assertion test for NotFoundException within tests/Unit/CompositePsrContainerOverYiisoftTest.php has been updated to match the changes in the NotFoundException class.

• Improved Test Coverage
  In the tests/Unit/ContainerTest.php file, new test cases have been introduced for the NotFoundException class. The previous test cases have also been revised for better test coverage.