Typos found with codespell

[Akuli]

Nothing major here, but I ran codespell Lib/ and found a few typos. I will submit pull requests next.

                # here drained task ouside the barrier
                                    ^^^^^^

                # wit here to reach the `parties`
                  ^^^

        # signal.signal() can throw if the "main thread" doensn't have signals enabled
                                                         ^^^^^^^^

        # readline module is loaded, since test_builtin is not intented to test
                                                               ^^^^^^^^

        # When running under regtest, a seperate tempdir is used
                                        ^^^^^^^^

        invokations = []
            invokations.append(src)
        self.assertEqual(len(invokations), 9)

        trough that corresponds to VALUE or the current value if None is
        ^^^^^^

        # Parameterizes an already-parameterized object.
          ^^^^^^^^^^^^^

        """Parameterizes a generic class.
           ^^^^^^^^^^^^^

[gvanrossum]

FWIW I'll approve this because you're a regular contributor, but in general such PRs are low value (none of the typos I saw you reported hampered understanding of the comment), so please don't do this.