minor #19573 [Config] be more specific about bool env var processor (javaDeveloperKid)

This PR was submitted for the 7.0 branch but it was merged into the 6.4 branch instead.

Discussion
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[Config] be more specific about bool env var processor

Previous wording was not accurate enough for me because only 0 and 0.0 as integer and float respectively was presented. Alternative change could be:

> and all numbers except `0`, `0.0`, `'0'` and `'0.0'`

Let me know if the latter fits better for you.

Commits
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20e562e be more specific about bool env var processor

Author: javiereguiluz

configuration/env_var_processors.rst

@@ -105,7 +105,7 @@ Symfony provides the following env var processors:
 
 ``env(bool:FOO)``
     Casts ``FOO`` to a bool (``true`` values are ``'true'``, ``'on'``, ``'yes'``
-    and all numbers except ``0`` and ``0.0``; everything else is ``false``):
+    and all numbers (also of a string type) except ``0`` and ``0.0``; everything else is ``false``):
 
     .. configuration-block::