Add Path Validation and Environment Loading to TreeNode Class

[qisijia367]

This pull request introduces path validation and environment loading functionality to the TreeNode class. The changes ensure that the path provided during initialization is valid and that environment variables can be correctly loaded into the node's environment.

[codecov]

Codecov Report

Attention: Patch coverage is 31.91489% with 32 lines in your changes missing coverage. Please review.

Project coverage is 54.47%. Comparing base (6b55d5a) to head (273de37).
Report is 4 commits behind head on master.

Files with missing lines	Patch %	Lines
avocado/core/tree.py	31.91%	32 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6064      +/-   ##
==========================================
+ Coverage   54.46%   54.47%   +0.01%     
==========================================
  Files         202      202              
  Lines       21883    21928      +45     
==========================================
+ Hits        11919    11946      +27     
- Misses       9964     9982      +18     

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[richtja]

Hi @qisijia367, thank you very much for these changes, contributions are always welcome. Unfortunately, your patch changes TreeNode behaviour because it doesn't count with corner case where the path is only the root path / which is valid.

Can you please update your patch to respect the root path? Also, can you please add test which will tests the behaviour of TreeNodeEnvOnly with path ending with /?Thank you.

[qisijia367]

Hi @richtja,Thank you for your suggestions, I have optimized the code again and added some test cases in selftests/unit/tree.py. Please check if they meet the requirements.