(HistList.pas) Length of string with length() and SetLength instead of char at index 0
<h3><details><summary>Original Reporter info from Mantis: <small>jc99</small></summary><small>
- **Reporter name:** Joe care
</small></details></h3>
## Description:
Handling the length of a string should be done with setlength and length.
## Additional information:
Patch provided <br/>
``` & UnitTest```<br/>
## Mantis conversion info:
- **Mantis ID:** 37777
- **OS:** Win64
- **OS Build:** 10
- **Build:** latest
- **Platform:** x86-64
- **Version:** 3.3.1
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