fix: mitigate storing password in the memory

[pj892031]

Description

In Java is a known issue that passwords stored as String are not under control. It can be minimized by using char arrays instead of String. It will not completely solve the issue, just reduce it a little bit. This PR changes the password stored as a string into array of chars where possible.

Type of change

Please delete options that are not relevant.

• (fix) Bug fix (non-breaking change which fixes an issue)
• (refactor) Refactor the code

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas. In JS I did provide JSDoc
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• The java tests in the area I was working on leverage @nested annotations
• Any dependent changes have been merged and published in downstream modules

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
3 Code Smells

86.2% Coverage
0.0% Duplication

[JirkaAichler]

Looks good