Upgrade Python and PG in /.circleci/config.yml to be consistent with runtime version

[hcaofec]

Summary

This is a follow-up ticket from #4332.

Currently, Python 3.7.8 and Postgresql 10.13 are running on server and local. This does not match the version in circleci. Upgrade may be needed in circleci.

https://github.com/fecgov/openFEC/blob/develop/.circleci/config.yml#L11

      # Python
      - image: circleci/python:3.7.4-buster
        environment:
          TZ: America/New_York
          SQLA_TEST_CONN: postgresql://postgres@0.0.0.0/cfdm_unit_test

      # PostgreSQL
      - image: circleci/postgres:9.6.8
        environment:
          POSTGRES_USER: postgres
          POSTGRES_DB: cfdm_unit_test

From @rjayasekera, If you want to know the currently running version. Currently automatically updated but as of 9/18 version 10.11)

• run psql

select AURORA_VERSION();
select version();

Completion criteria:

• Update circleci python version to equal python at production runtime
• Update circleci postgres version to equal what we're running in aurora

[jason-upchurch]

@hcaofec nice catch! I was working the cms version of #4332 and was about to open the same issue. I see that #4332 specifies 10.7 rather than 10.13 however.

[fec-jli]

@hcaofec nice catch! I was working the cms version of #4332 and was about to open the same issue. I see that #4332 specifies 10.7 rather than 10.13 however.

@jason-upchurch good question. our Aurora postgres version is 10.7 on cloud (only support 10.7 so far). 10.13 is on local ( the latest version), I think it is fine for now.

[pkfec]

The latest docker images for circleci can be found here #https://circleci.com/docs/2.0/docker-image-tags.json. Updated the Python and Postgres docker images files in circleci/config.yml file.

PR #4648 is ready for review