Fix `simple_format` undefined error #60179

What does this MR do?

It fixes #60179 (closed)

I took a look on Rails source code and I found that simple_format is not defined in ActionView::Helpers::TagHelper, however it is actually located in ActionView::Helpers::TextHelper. Also TagHelper is a part of TextHelper (see here)

The solution is to include TextHelper instead of TagHelper. That should be enough to resolve the described problem.

I've added tests to cover the code where simple_format is called.

It's my first MR to GitLab, please let me know if something is missing or requires a change.

Thanks!

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
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• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

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