bug#28781: 25.3; Override erroneous "incorrect verb voice" from checkdoc

[Radon Rosborough <radon.neon@gmail.com>]

I have the following definition:

    (defmacro straight--functionp (object)
      "Non-nil if OBJECT, an unquoted symbol, evaluates to a function.
    However, if OBJECT evaluates to its own symbol value or t, then
    return nil. This is useful for allowing a function to be called
    with nil, non-nil, or a function object, without worrying about
    the non-nil value being interpreted as a function: just call the
    function with the quoted name of the argument, or use t."
      (let ((object-sym (make-symbol "object")))
        `(let ((,object-sym ,object))
           (and (not (memq ,object-sym '(,object t)))
                (functionp ,object-sym)))))

M-x checkdoc reports the following on the first line:

    Probably "evaluates" should be imperative "evaluate"

This is wrong. How can I suppress this spurious warning, other than by
rewording the docstring? I know that checkdoc has
`checkdoc-symbol-words' for suppressing spurious warnings about unquoted
symbols, but there appears to be nothing similar I can customize in
file-local variables for this case.