Update Python base version to 3.7+

[npradeep357]

Updated Python version to 3.7+ as 3.6 came to end-of-life support. Updated tests
related to #128

[npradeep357]

@ccordoba12, updated Python version to 3.7+ and removed python 3.6 slots on Github actions.
Please approve workflows

[npradeep357]

@ccordoba12 or @krassowski or authors, I see issue in static code analysis checks but I think that's not related to this PR. It says validate JSON schema check failed. I just updated the static.yml to use python 3.7 but not sure what's happening?
Can someone point out to me what's the issue here.

Thank you

[npradeep357]

Only difference is that the static checks now use py 3.7 instead of 3.6.
Will jsonschema won't work as is in 3.7? or Is there a syntax change?

[ccordoba12]

@krassowski, could you check what's happening with jsonchema?

[krassowski]

I opened python-jsonschema/jsonschema#889. A workaround for now would be to pass an empty instance of settings schema (weather through standard input or from a file).

[ccordoba12]

I opened python-jsonschema/jsonschema#889.

Thanks for your help @krassowski!

A workaround for now would be to pass an empty instance of settings schema (weather through standard input or from a file).

What do you mean by this?

[krassowski]

I mean something like:

echo "{}" | jsonschema pylsp/config/schema.json

because an empty instance (empty settings) are acceptable, so they will pass validation.

Alternatively we could pin a 3.x version. Ether should solve the problem on the CI for now.

[npradeep357]

Updated jsonschema test as mentioned by @krassowski. Now the tests pass.
@krassowski or @ccordoba12 can you please review and approve this PR.

Thank you

[krassowski]

Looks good to me. Thanks! I don't know if we want to merge immediately or wait until the EOL of Python 3.6 (23 Dec 2021).

[krassowski]

Merging as Python 3.6 reached EOL yesterday.