fix: validate JWT signed other implemenation

[lukasjhan]

I added private field in JWT class. It is set when we created JWT instance from encoded. And I created getUnsignedToken method to use encoded jwt string when it is existed.

It close #157

[codecov[bot]]

Codecov Report

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

Project coverage is 98.03%. Comparing base (d9eaf44) to head (982a06a).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## next #158 +/- ## ========================================== + Coverage 97.81% 98.03% +0.21% ========================================== Files 23 23 Lines 2062 2082 +20 Branches 295 307 +12 ========================================== + Hits 2017 2041 +24 + Misses 45 41 -4 ```

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[cre8]

@lukasjhan code looks good, can you add missing tests before merging?

[lukasjhan]

Okay :) I'm working on it

[c2bo]

error - 2024-03-11 13:57:57,128 -- Commit creating failed: {"detail":"Tokenless has reached GitHub rate limit. Please upload using a token: https://docs.codecov.com/docs/adding-the-codecov-token. Expected available in 545 seconds."}
Error: Codecov: Failed to properly create commit: The process '/home/runner/work/_actions/codecov/codecov-action/v4/dist/codecov' failed with exit code 1

[lukasjhan]

error - 2024-03-11 13:57:57,128 -- Commit creating failed: {"detail":"Tokenless has reached GitHub rate limit. Please upload using a token: https://docs.codecov.com/docs/adding-the-codecov-token. Expected available in 545 seconds."}
Error: Codecov: Failed to properly create commit: The process '/home/runner/work/_actions/codecov/codecov-action/v4/dist/codecov' failed with exit code 1

There is a token. It's strange. We're trying to find out why.