like / nlike_utf8 do not allow escaping %

[Dandandan]

Describe the bug

like_utf8 and nlike_utf8 and scalar variants don't take care of escaping the wildcard character.

To Reproduce

    test_utf8_scalar!(
        test_utf8_scalar_escape,
        vec!["a%", "a\\x"],
        "a\\%",
        like_utf8_scalar,
        vec![true, false]
    );

This fails in master, returning false / true.

Expected behavior
A clear and concise description of what you expected to happen.

Additional context
Add any other context about the problem here.

[alamb]

Another reproducer from @jwdeitch on #1087

    test_utf8!(
        ilike_utf8_scalar_regex,
        vec!["%%%"],
        vec![r#"\%_\%"#],
        ilike_utf8,
        vec![true]
    );

[daniel-martinez-maqueda-sap]

I have a proposal I've been working on that could work:

• Escape regex patterns calling escape from the crate regex as it is done at the moment
• If a like wildcard is escaped, remove the escape characters (so that it is matched when running the regex)