fix: support special characters and invalid ignore rules when filtering files

[j-luong]

This PR fixes a code file filtering issue by adding support for ignoring ignore rules that are not valid when constructing the filter rules for native code scans.

For example, a .gitignore file with . is not a valid rule and will be skipped when building the glob patterns for file filtering.

This option was chosen as the parser accepts multiple types of ignore files (e.g. .gitignore, .snyk), which may have slightly different syntax.

This PR also fixes cases where .gitignore file contains rules with special characters, e.g. *$ should now work as expected.

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[snyk-io]

✅ Snyk checks have passed. No issues have been found so far.

Status	Scanner	Critical	High	Medium	Low	Total (0)
✅	Open Source Security	0	0	0	0	0 issues
✅	Licenses	0	0	0	0	0 issues
✅	Code Security	0	0	0	0	0 issues

💻 Catch issues earlier using the plugins for VS Code, JetBrains IDEs, Visual Studio, and Eclipse.

[PeterSchafer]

Since this implementation is about creating parity with the git behaviour, maybe we can consider a comparison test? I can imagine that this uncovers some more discrepancies?