feat(magic): support PRQL query in line magic

[eitsupi]

Supports execution of PRQL queries in line magic, like that.

results = %prql from p = `products.csv` | aggregate [min unitsInStock, max unitsInStock]

This PR also changes the function that performs argument parsing from sql.parse.magic_args to IPython.core.magic_arguments.parse_argstring.
In SQL we need to use sql.parse.magic_args because the comment character is -- in SQL. In PRQL, we do not need to consider --.
IPython.core.magic_arguments.parse_argstring is more strict and will raise an error for unsupported arguments such as --foo.

In [1]: %load_ext pyprql.magic

In [2]: %prql --foo from a
UsageError: unrecognized arguments: --foo

[max-sixty]

Really good, thank you very much @eitsupi !