fix: View::renderSection() return type

[kenjis]

Description
From https://forum.codeigniter.com/showthread.php?tid=91082

The method should not use echo, because it has side effects.

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]

The bug is old. I came across this a long time ago, not a serious mistake and I agreed with it.
Do you need a return test? For example,
$section = $this->renderSection(”content") ?? ”Not content";

[kenjis]

Added a test.

[neznaika0]

Good

[ricctram]

ok thank you @kenjis .. do you think Is better to wait the 4.6.0 then?

[kenjis]

If you want this soon, patch system/View/View.php by yourself.
https://github.com/codeigniter4/CodeIgniter4/pull/8965/files#diff-4a0d588299e7596abc008b8c30cfbbdd51be730d1a8ddf945704a5efcbb68cec
As you see, the change is only in it.