Merge pull request #5837 from kenjis/fix-docs-changelog-v4.2.0

docs: add index.php/spark changes in changelog

Author: samsonasik

user_guide_src/requirements.txt

@@ -2,3 +2,4 @@ sphinx>=2.4.4,<3
 sphinxcontrib-phpdomain>=0.7.1
 docutils>=0.16
 sphinx-rtd-theme>=0.5.0
+jinja2<3.1

user_guide_src/source/changelogs/v4.2.0.rst

@@ -13,6 +13,9 @@ BREAKING
 ********
 
 - The method signature of ``Validation::setRule()`` has been changed. The ``string`` typehint on the ``$rules`` parameter was removed. Extending classes should likewise remove the parameter so as not to break LSP.
+- The ``CodeIgniter\CodeIgniter`` class has a new property ``$context`` and it must have the correct context at runtime. So the following files have been changed:
+    - ``public/index.php``
+    - ``spark``
 
 Enhancements
 ************