Allow dots in dict_path predicate

[cukiernick]

I'd like to identify list element based on a key with dots in the string.

def test_dict_path():
    d = dict(
        neighbors = [
            dict(ip="1.1.1.1", prefix="a"),
            dict(ip="2.2.2.2", prefix="b"),
        ],
        foo="bar",
    )

    path = to_path("neighbors[ip=2.2.2.2].prefix")
    assert path.get_element(d) == "b"

raised error:

inp = 'neighbors[ip=2'

    def parse_element(inp: str) -> WildDictPath:
        for subtype in cls.element_types:
            parsed = subtype.parse(inp)
            if parsed is not None:
                return parsed
>       raise InvalidPathException(f"Could not parse path segment {inp}")
E       inmanta.util.dict_path.InvalidPathException: Could not parse path segment neighbors[ip=2

[wouterdb]

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