Add better typing in jinja_static.py

[peterallenwebb]

Added type annotations. Cleaned up.

Checklist

• [x] I have read the contributing guide and understand what's expected of me.
• [x] I have run this code in development, and it appears to resolve the stated issue.
• [x] This PR includes tests, or tests are not required or relevant for this PR.
• [x] This PR has no interface changes (e.g., macros, CLI, logs, JSON artifacts, config files, adapter interface, etc.) or this PR has already received feedback and approval from Product or DX.
• [x] This PR includes type annotations for new and modified functions.

[github-actions[bot]]

Thank you for your pull request! We could not find a changelog entry for this change. For details on how to document a change, see the contributing guide.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 91.66667% with 1 line in your changes missing coverage. Please review.

Project coverage is 89.15%. Comparing base (5db0b81) to head (7fe927c). Report is 4 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #10835 +/- ## ========================================== - Coverage 89.15% 89.15% -0.01% ========================================== Files 183 183 Lines 23418 23422 +4 ========================================== + Hits 20878 20881 +3 - Misses 2540 2541 +1 ``` | [Flag](https://app.codecov.io/gh/dbt-labs/dbt-core/pull/10835/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dbt-labs) | Coverage Δ | | |---|---|---| | [integration](https://app.codecov.io/gh/dbt-labs/dbt-core/pull/10835/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dbt-labs) | `86.37% <91.66%> (-0.01%)` | :arrow_down: | | [unit](https://app.codecov.io/gh/dbt-labs/dbt-core/pull/10835/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dbt-labs) | `62.11% <66.66%> (+<0.01%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dbt-labs#carryforward-flags-in-the-pull-request-comment) to find out more. | [Components](https://app.codecov.io/gh/dbt-labs/dbt-core/pull/10835/components?src=pr&el=components&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dbt-labs) | Coverage Δ | | |---|---|---| | [Unit Tests](https://app.codecov.io/gh/dbt-labs/dbt-core/pull/10835/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dbt-labs) | `62.11% <66.66%> (+<0.01%)` | :arrow_up: | | [Integration Tests](https://app.codecov.io/gh/dbt-labs/dbt-core/pull/10835/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dbt-labs) | `86.37% <91.66%> (-0.01%)` | :arrow_down: |