Function get_syntax_root_and_diagnostics_from_file 

pub fn get_syntax_root_and_diagnostics_from_file(
    db: &SimpleParserDatabase,
    cairo_filepath: PathBuf,
) -> (SyntaxNode<'_>, Diagnostics<'_, ParserDiagnostic<'_>>)

Reads a Cairo file to the DB and returns the syntax_root and diagnostics of its parsing.