[ BB2-726 ] Upgrade Pillow to 8.3.1

[njdister]

JIRA Ticket:
BB2-726

User Story or Bug Summary:
Upgrade Pillow as a result of vulnerability found in Snyk

What Does This PR Do?

This PR simply replaces Pillow 8.2.0 with 8.3.1. There is some restructuring of requirements.txt files due to the newer python / pip version this was compiled with, but hashes only change for Pillow upon inspection.

What Should Reviewers Watch For?

N/A

What Security Implications Does This PR Have?

Submitters should complete the following questionnaire:

• If the answer to any of the questions below is Yes, then here's a link to the associated Security Impact Assessment (SIA), security checklist, or other similar document in Confluence: N/A.
  • Does this PR add any new software dependencies? No.
  • Does this PR modify or invalidate any of our security controls? No.
  • Does this PR store or transmit data that was not stored or transmitted before? No.
• If the answer to any of the questions below is Yes, then please add @StewGoin as a reviewer, and note that this PR should not be merged unless/until he also approves it.
  • Do you think this PR requires additional review of its security implications for other reasons? No.

What Needs to Be Merged and Deployed Before this PR?

N/A

Submitter Checklist

I have gone through and verified that...:

• This PR is reasonably limited in scope, to help ensure that:
  1. It doesn't unnecessarily tie a bunch of disparate features, fixes, refactorings, etc. together.
  2. There isn't too much of a burden on reviewers.
  3. Any problems it causes have a small "blast radius".
  4. It'll be easier to rollback if that becomes necessary.
• I have named this PR and its branch such that they'll be automatically be linked to the (most) relevant Jira issue, per: https://confluence.atlassian.com/adminjiracloud/integrating-with-development-tools-776636216.html.
• This PR includes any required documentation changes, including README updates and changelog / release notes entries.
• All new and modified code is appropriately commented, such that the what and why of its design would be reasonably clear to engineers, preferably ones unfamiliar with the project.
• All tech debt and/or shortcomings introduced by this PR are detailed in TODO and/or FIXME comments, which include a JIRA ticket ID for any items that require urgent attention.
• Reviews are requested from both:
  • At least two other engineers on this project, at least one of whom is a senior engineer or owns the relevant component(s) here.
  • Any relevant engineers on other projects (e.g. BFD, SLS, etc.).
• Any deviations from the other policies in the DASG Engineering Standards are specifically called out in this PR, above.
  • Please review the standards every few months to ensure you're familiar with them.

[dtisza1]

The changes look good to me!

I ran tests locally and they passed OK. I tried out some JPG logo image updates in the UI and they worked as expected.

[JFU-GIT]

the dependencies changes look good.