minor #7605 Fix typo (GabrielCW)

This PR was submitted for the 3.2 branch but it was merged into the 2.7 branch instead (closes #7605).

Discussion
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Fix typo

The docs says the option must be prefixed with a "double slash" (`//`) when it should be "double dash" `--`.

Commits
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1c5423a Fix typo

Author: xabbuh

console.rst

@@ -237,7 +237,7 @@ console::
                 // pass arguments to the helper
                 'username' => 'Wouter',
 
-                // prefix the key with a double slash when passing options,
+                // prefix the key with two dashes when passing options,
                 // e.g: '--some-option' => 'option_value',
             ));