Minor Upgrade to CVXPY to avoid possible 2to3 Error

[fabianlim]

Problem:

When doing pip install -e ., we may get a error in cvxpy setup command: use_2to3 is invalid. error when installing the cvxpy==1.0.31 wheel. This is because the newer setuptools have 2to3 removed

https://github.com/pypa/setuptools/issues/2086

Possible Solution:

The cvxpy>=1.1 versions do not depend on 2to3. Hence we can bump to the nearest version 1.1.0, which is very close to the current version 1.0.31. There exist only alpha versions in between them

1.0.31, 1.1.0a0, 1.1.0a1, 1.1.0a2, 1.1.0a3, 1.1.0a4, 1.1.0

[vijay-arya]

Thanks @fabianlim