Update Expression.rst

[bedfir]

The === operator, which checks for strict equality, is fully supported and can be used to ensure that both the value and type are identical. as discussed with @stof

[xabbuh]

Wäre did you read that there is a === in the expression language?

[stof]

@xabbuh here: https://github.com/symfony/symfony/blob/a13836096a832ec185ccc0ba520433772e9e2c9f/src/Symfony/Component/ExpressionLanguage/Parser.php#L57

[stof]

And while I thought it was added later, it has actually always been part of it: symfony/symfony@9d98fa2#diff-213c715dc90e4ff7b4ea28e4eb30e7a553f2085a9a4fd7e7ee1b80544eaee8d6R54

[bedfir]

I think I misunderstood the doc.
i understood that strict equality === doesn't work with expressions.