ci: pull the version number from the pyproject manifest

[tangowithfoxtrot]

📔 Objective

When working on #1332, I noticed that the zip artifacts still used 0.1.0 in the filename because it was deriving the version from the bitwarden-py cargo file. This PR updates it so that it derives the Python SDK version from the pyproject manifest instead.

⏰ Reminders before review

• Contributor guidelines followed
• All formatters and local linters executed and passed
• Written new unit and / or integration tests where applicable
• Protected functional changes with optionality (feature flags)
• Used internationalization (i18n) for all UI strings
• CI builds passed
• Communicated to DevOps any deployment requirements
• Updated any necessary documentation (Confluence, contributing docs) or informed the documentation team

🦮 Reviewer guidelines

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• 📝 (:memo:) or ℹ️ (:information_source:) for notes or general info
• ❓ (:question:) for questions
• 🤔 (:thinking:) or 💭 (:thought_balloon:) for more open inquiry that's not quite a confirmed issue and could potentially benefit from discussion
• 🎨 (:art:) for suggestions / improvements
• ❌ (:x:) or ⚠️ (:warning:) for more significant problems or concerns needing attention
• 🌱 (:seedling:) or ♻️ (:recycle:) for future improvements or indications of technical debt
• ⛏ (:pick:) for minor or nitpick changes

[sonarqubecloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions[bot]]

Checkmarx One – Scan Summary & Details – 960db2cd-034c-4714-873b-5041d3c304eb

Great job! No new security vulnerabilities introduced in this pull request

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 7.32%. Comparing base (d41bdaf) to head (6260f60).

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #1333   +/-   ##
=====================================
  Coverage   7.32%   7.32%           
=====================================
  Files         20      20           
  Lines       1378    1378           
=====================================
  Hits         101     101           
  Misses      1277    1277           

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[tangowithfoxtrot]

I could also update the version in the bitwarden-py cargo file, but since we don't publish this anywhere, it seems to make more sense to use ./languages/python/pyproject.toml, since that is what the published Python package will use as its version.