Apply cpython patch bpo-39492 for the reference counting issue in pickle5

[suquark]

Why are these changes needed?

This should fix cloudpipe/cloudpickle#343 for python3.5, 3.6 and 3.7
It doesn't fix python3.8, but there will be official python3.8.2 fix

Related issue number

Checks

• I've run scripts/format.sh to lint the changes in this PR.
• I've included any doc changes needed for https://ray.readthedocs.io/en/latest/.
• I've made sure the tests are passing. Note that there might be a few flaky tests, see the recent failure rates at https://ray-travis-tracker.herokuapp.com/.

[suquark]

I think we also need to add a test in Ray, although all tests passed in the upstream

[AmplabJenkins]

Can one of the admins verify this patch?

[AmplabJenkins]

Test FAILed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/Ray-PRB/21969/
Test FAILed.

[edoakes]

Thanks for fixing this so quickly. This is great.

[AmplabJenkins]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/Ray-PRB/21987/
Test PASSed.

[AmplabJenkins]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/Ray-PRB/21992/
Test PASSed.

[AmplabJenkins]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/Ray-PRB/21995/
Test PASSed.

[suquark]

The CI error seems irrelevant. I am going to merge this PR.