Fix glob pattern to correctly ignore directories with only dots

[pi55man]

This PR addresses issue #2990, where ripgrep did not properly ignore directories named only with dots (e.g., ., .., ...) when using negated glob patterns (-g '!dir').

Previously, the file_name function in globset only checked if the last byte was a dot (.), which led to incorrect behavior. This caused:

• rg --files -g '!asdf.' still listing asdf./foo
• But rg --files -g '!asdf' correctly ignoring asdf/foo

Fix

The function now ensures that entire filenames made only of dots are ignored by using:

if path.iter().all(|&b| b == b'.') {
    return None;
}