Fix code scanning alert no. 7: Use of a broken or risky cryptographic algorithm

[HTHou]

Fixes https://github.com/apache/tsfile/security/code-scanning/7

To fix the problem, we should replace the use of the MD5 algorithm with a stronger, modern cryptographic hash function such as SHA-256. This change will enhance the security of the cryptographic operations performed by the code.

• Replace MessageDigest.getInstance("MD5") with MessageDigest.getInstance("SHA-256").
• Ensure that the rest of the code correctly handles the output size of SHA-256, which is 256 bits (32 bytes), compared to MD5's 128 bits (16 bytes).

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 63.63%. Comparing base (6c4f911) to head (ad1a4b0).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #286 +/- ## ======================================== Coverage 63.63% 63.63% ======================================== Files 501 501 Lines 31787 31787 Branches 4110 4110 ======================================== Hits 20228 20228 Misses 11082 11082 Partials 477 477 ```

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