Issue #26034: Sync documentation of --clear with its behavior

Most of the docs has already been updated in c3c188a0325a.
diff --git a/Doc/using/venv-create.inc b/Doc/using/venv-create.inc
index 02bcbee..0873a99 100644
--- a/Doc/using/venv-create.inc
+++ b/Doc/using/venv-create.inc
@@ -45,9 +45,8 @@
                              are not the default for the platform.
       --copies               Try to use copies rather than symlinks, even when
                              symlinks are the default for the platform.
-      --clear                Delete the environment directory if it already exists.
-                             If not specified and the directory exists, an error is
-                             raised.
+      --clear                Delete the contents of the environment directory if it
+                             already exists, before environment creation.
       --upgrade              Upgrade the environment directory to use this version
                              of Python, assuming Python has been upgraded in-place.
       --without-pip          Skips installing or upgrading pip in the virtual