minor #20144 fix ref syntax (xabbuh)

This PR was merged into the 6.4 branch.

Discussion
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fix ref syntax

replaces #20140

Commits
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3ee2dae fix ref syntax

Author: xabbuh

components/expression_language.rst

@@ -82,7 +82,7 @@ Null Coalescing Operator
 
 .. note::
 
-    This content has been moved to the ref:`null coalescing operator <component-expression-null-coalescing-operator>`_
+    This content has been moved to the :ref:`null coalescing operator <component-expression-null-coalescing-operator>`
     section of ExpressionLanguage syntax reference page.
 
 Parsing and Linting Expressions