Function resolve_alias

fn resolve_alias(
    alias_map: &[(String, String)],
    time_index: &HashSet<String>,
) -> HashSet<String>

Resolves alias of the time index column.

i.e if a is time index, alias= {a:b, b:c}, then result should be {a, b}(not {a, c}) because projection is not transitive if alias={b:a} and a is time index, then return empty