minor symfony#25207 [HttpKernel] remove upgrade instructions for kernel.root_dir (xabbuh)

This PR was merged into the 3.3 branch.

Discussion
----------

[HttpKernel] remove upgrade instructions for kernel.root_dir

| Q             | A
| ------------- | ---
| Branch?       | 3.3
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

Commits
-------

9897da4 remove upgrade instructions for kernel.root_dir

Author: fabpot

UPGRADE-3.3.md

@@ -254,12 +254,6 @@ HttpFoundation
 HttpKernel
 -----------
 
- * Deprecated the `kernel.root_dir` parameter. Use the new `kernel.project_dir`
-   parameter instead.
-
- * Deprecated the `Kernel::getRootDir()` method. Use the new `Kernel::getProjectDir()`
-   method instead.
-
  * The `Extension::addClassesToCompile()` and `Extension::getClassesToCompile()` methods have been deprecated and will be removed in 4.0.
 
  * The `Psr6CacheClearer::addPool()` method has been deprecated. Pass an array

UPGRADE-4.0.md

@@ -361,12 +361,6 @@ HttpFoundation
 HttpKernel
 ----------
 
- * Removed the `kernel.root_dir` parameter. Use the `kernel.project_dir` parameter
-   instead.
-
- * Removed the `Kernel::getRootDir()` method. Use the `Kernel::getProjectDir()`
-   method instead.
-
  * The `Extension::addClassesToCompile()` and `Extension::getClassesToCompile()` methods have been removed.
 
  * Possibility to pass non-scalar values as URI attributes to the ESI and SSI