fix: make the search case-insensitive

[michalsn]

Description
This PR makes the search functionality case-insensitive.

Fixes #14

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide

[neznaika0]

Fast fix 😄
I added mb_strtolower(), but now the first character doesn't work when searching: REMOVING -> fail, EMOVING -> ok.

Everything is fine with the other file "Registering Account" (ReGiSte -> ok). Is there some kind of cache in the system?

[neznaika0]

It seems the search uses the content inside, not the filename. But then why does it find "emoving"? There is no word "removing" inside. Wonders

[michalsn]

Can you paste here the entire content of the file (as code), plus the filename? I will check it out later.

[neznaika0]

It from forum lonnieezell. https://github.com/lonnieezell/forum-example/tree/develop/help

[michalsn]

It should work now.

[neznaika0]

Fine! I don't see where this is implemented, but the content search seems to be working: GENeral -> ok

[michalsn]

Here, we check the file name.

[michalsn]

Thanks for the feedback!