Revert "feature symfony#11802 [Process] allow writing "prepared" command line. (Simperfit)"

This reverts commit a316cd5, reversing
changes made to cdc0bb7.

Author: nicolas-grekas

components/process.rst

@@ -368,27 +368,6 @@ instead::
     );
     $process->run();
 
-Using a Prepared Command Line
------------------------------
-
-You can run the process by using a a prepared command line using the
-double bracket notation. You can use a placeholder in order to have a
-process that can only be changed with the values and without changing
-the PHP code::
-
-    use Symfony\Component\Process\Process;
-
-    $process = Process::fromShellCommandline('echo "$name"');
-    $process->run(null, ['name' => 'Elsa']);
-
-.. caution::
-
-    A prepared command line will not be escaped automatically!
-
-.. versionadded:: 4.4
-
-    Prepared command lines were introduced in Symfony 4.4.
-
 Process Timeout
 ---------------