Fix incorrect split UTF-8 strings

[vjik]

Q	A
Is bugfix?	✔️
New feature?	❌
Breaks BC?	❌
Fixed issues	-

[what-the-diff]

PR Summary

• Fix for StringHelper::split() method
  This PR includes a bug fix in the StringHelper::split() method which is documented in CHANGELOG.md. This fix makes sure that the function behaves as expected.

• Updates in the regular expression in StringHelper::split() method
  The regular expression used in the StringHelper::split() method has been improved. This change allows more accurate splitting of the string, which increases the overall performance of string handling within the codebase.

• Added new test case
  A new test case has been added in StringHelperTest.php. The addition of this test ensures that our StringHelper::split() method behaves correctly under various conditions, thus increasing the reliability of our software.

[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (e9cd0f9) 96.84% compared to head (eb403aa) 96.84%.
Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff            @@
##             master     #105   +/-   ##
=========================================
  Coverage     96.84%   96.84%           
  Complexity      114      114           
=========================================
  Files             4        4           
  Lines           317      317           
=========================================
  Hits            307      307           
  Misses           10       10           

Files Changed	Coverage Δ
src/StringHelper.php	93.63% <100.00%> (ø)

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.