Unable to read vector<long long>/vector<Long64_t> branches

[masonproffitt]

The type std::vector<long long> (or std::vector<Long64_t>) is missing from uproot's type interpretation:

>>> import uproot
>>> file = uproot.open('test_file.root')
>>> file['tree']['long64_t_vector_branch']
<TBranchElement b'long64_t_vector_branch' at 0x7f87add58250>
>>> file['tree']['long64_t_vector_branch'].array()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python3.8/site-packages/uproot/tree.py", line 1362, in array
    interpretation = self._normalize_interpretation(interpretation, awkward)
  File "/usr/lib/python3.8/site-packages/uproot/tree.py", line 1105, in _normalize_interpretation
    raise ValueError("cannot interpret branch {0} as a Python type\n   in file: {1}".format(repr(self.name), self._context.sourcepath))
ValueError: cannot interpret branch b'long64_t_vector_branch' as a Python type
   in file: /home/user/cern/iris/code/uproot_tree_utils/test_file.root

The type is missing in uproot/interp/auto.py. unsigned long long/ULong64_t works fine.