[BUGFIX] wrong codesnippet for registering CustomConditionFunctionsProvider is rendered (#6417) (#6418)

(cherry picked from commit a8ee18f)

Co-authored-by: Can Karadağ <60479637+can0199@users.noreply.github.com>
Co-authored-by: Can Adrian Karadag <can.karadag@bikar.com>

Author: 3 people

Documentation/ApiOverview/SymfonyExpressionLanguage/Index.rst

@@ -89,7 +89,7 @@ Additional functions
 Additional functions can be provided with another class that has to be
 registered in the provider:
 
-..  literalinclude:: _codesnippets/_CustomConditionFunctionsProvider.php
+..  literalinclude:: _codesnippets/_CustomTypoScriptConditionProvider.php
     :caption: EXT:my_extension/Classes/ExpressionLanguage/CustomTypoScriptConditionProvider.php
 
 The (artificial) implementation below calls some external URL based on given variables: