Run RPC JIT tests with variable type hints only in Python >=3.6 (#34284)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34284
Python 3.5 only supports function type hints.
Variable type hints are introduced in Python 3.6.
So these tests with JIT type hints will fail with "Syntax Error" in Python 3.5 environment.
ghstack-source-id: 99542199
Test Plan: `
Differential Revision: D7348891
fbshipit-source-id: c4c71ac021f35b5e6f7ce4d3e6af10dd1d2600cc
