docs: make Request::getEnv() deprecated

See b0975ec5dba#diff-fb41662a8e01f56cacc449d12f5d386be73835879b2f49f452cb2aef8ac03466R441-R442

Author: kenjis

system/HTTP/RequestTrait.php

@@ -203,9 +203,12 @@ public function getServer($index = null, $filter = null, $flags = null)
      * @param array|int|null    $flags
      *
      * @return mixed
+     *
+     * @deprecated 4.4.4 This method does not work from the beginning. Use `env()`.
      */
     public function getEnv($index = null, $filter = null, $flags = null)
     {
+        // @phpstan-ignore-next-line
         return $this->fetchGlobal('env', $index, $filter, $flags);
     }
 

user_guide_src/source/changelogs/v4.4.4.rst

@@ -41,6 +41,10 @@ Changes
 Deprecations
 ************
 
+- **Request:** The :php:meth:`CodeIgniter\\HTTP\\Request::getEnv()` method is
+  deprecated. This method does not work from the beginning. Use :php:func:`env()`
+  instead.
+
 **********
 Bugs Fixed
 **********

user_guide_src/source/incoming/incomingrequest.rst

@@ -131,6 +131,9 @@ The ``getServer()`` method will pull from ``$_SERVER``.
 getEnv()
 --------
 
+.. deprecated:: 4.4.4 This method does not work from the beginning. Use
+    :php:func:`env()` instead.
+
 The ``getEnv()`` method will pull from ``$_ENV``.
 
 * ``$request->getEnv()``

user_guide_src/source/incoming/request.rst

@@ -107,6 +107,9 @@ Class Reference
 
     .. php:method:: getEnv([$index = null[, $filter = null[, $flags = null]]])
 
+        .. deprecated:: 4.4.4 This method does not work from the beginning. Use
+            :php:func:`env()` instead.
+
         :param    mixed     $index: Value name
         :param    int       $filter: The type of filter to apply. A list of filters can be found in `PHP manual <https://www.php.net/manual/en/filter.filters.php>`__.
         :param    int|array $flags: Flags to apply. A list of flags can be found in `PHP manual <https://www.php.net/manual/en/filter.filters.flags.php>`__.