When searching text inside editor, Capital Turkish character 'I' not working

### Apache NetBeans version

Apache NetBeans 17

### What happened

I cannot use find on editor for search-text that contains I.

### How to reproduce

When editing a java file, with a line "... public static boolean is_FILENAME_START( ..."
- I pressed CTRL+F to search a text, inside the java file.
- I wrote a search-text with a capital turkish character. For example "FILE" that contains a big 'I'
- When i press enter, the status bar says "file not found or taking too long to search"
- When I wrote a search-text with "file", it founds.

### Did this work correctly in an earlier version?

No / Don't know

### Operating System

Microsoft Windows [Version 10.0.22621.1265] Turkish

### JDK

OpenJDK 64-Bit Server VM Temurin-19.0.1+10 (build 19.0.1+10, mixed mode, sharing)

### Apache NetBeans packaging

Apache NetBeans provided installer

### Anything else


### Are you willing to submit a pull request?

No

Reproduce the editor search through Ctrl+F while editing a Java file on a Turkish Windows installation, using “FILE” and “file” as the search text. Start from the editor’s find behavior and the status-bar result; done means the uppercase Turkish character search finds the matching text instead of reporting it as missing or too slow.

Written by the indexing model from the issue text.