treebuilder: fix file resource leaks

[yueyuankun]

1. File resource leak risk : Fixed file handling issues in the generate_module_info() function
2. Code quality improvement : Used context managers to ensure proper file closure

[coveralls]

Pull Request Test Coverage Report for Build 23483124560

Details

• 0 of 6 (0.0%) changed or added relevant lines in 1 file are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.04%) to 41.561%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/pylorax/treebuilder.py	0	6	0.0%

Files with Coverage Reduction	New Missed Lines	%
src/pylorax/treebuilder.py	1	40.2%

Totals
Change from base Build 22962972632:	-0.04%
Covered Lines:	1643
Relevant Lines:	3914

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💛 - Coveralls

[bcl]

Looks good, thanks!