minor symfony#7957 Minor reword of code contribution standards (javiereguiluz)

This PR was merged into the 2.7 branch.

Discussion
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Minor reword of code contribution standards

This fixes symfony#7956.

Commits
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1426a10 Minor reword of code contribution standards

Author: xabbuh

contributing/code/standards.rst

@@ -186,7 +186,7 @@ Naming Conventions
 * Use camelCase, not underscores, for variable, function and method
   names, arguments;
 
-* Use underscores for option names and parameter names;
+* Use underscores for configuration options and parameters;
 
 * Use namespaces for all classes;