Fix code scanning alert no. 103: Partial path traversal vulnerability from remote

[fugerit79]

Fixes https://github.com/fugerit-org/fj-doc/security/code-scanning/103

To fix the partial path traversal vulnerability, we need to ensure that the base directory path (tempDir) is slash-terminated before checking if the user-supplied path (file) starts with it. This can be achieved by modifying the checkIfInTempFolder method to use toPath().normalize() for both the base directory and the user-supplied path, which provides a more robust way to check if one path is a subdirectory of another.

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[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

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