chore: deprecate support for python 3.9

[VebjornG]

Description

Deprecate support for python 3.9 in order to introduce scipy 1.14 and numpy 2.0

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• Refactor (non-breaking change which improves implementation)
• Performance (non-breaking change which improves performance. Please add associated performance test and results)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Non-functional change (xml comments/documentation/etc)

Contributor Checklist:

• My code follows the code style of this project.
• I have added an example of my new feature and included it in the documentation.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.
• My Pull Request name follows the naming convention fix: <description>, feat: <description>, etc.

Reviewer Checklist for Charts compliant functions:

• The docstrings of the new function follow the contributing guidelines.
• The new function is professionally documented
• The new function and associated scripts are covered by one or more unit tests and code coverage did not decrease.
• The new function is accompanied by an example and it is included in the Gallery of Charts.
• The new function is reviewed in Chromatic. Access the storybook build results url and comment, approve or deny.
• All function inputs, arguments, and outputs have a supported data type and have human readable names.
• No code language is included in the description of the function or parameters (e.g use "polynomial order" instead of "poly_order")

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.25%. Comparing base (39ed9e7) to head (ded1e76).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #275      +/-   ##
==========================================
- Coverage   91.27%   91.25%   -0.03%     
==========================================
  Files         106      106              
  Lines        3863     3863              
  Branches      839      839              
==========================================
- Hits         3526     3525       -1     
  Misses        208      208              
- Partials      129      130       +1     

see 1 file with indirect coverage changes

[github-actions]

Unit Test Results

    15 files   -     6      15 suites   - 6   26m 18s ⏱️ - 10m 44s
 1 114 tests ±    0   1 114 ✅ ±    0  0 💤 ±0  0 ❌ ±0 
10 995 runs   - 4 779  10 986 ✅  - 4 777  9 💤  - 2  0 ❌ ±0 

Results for commit ded1e76. ± Comparison against base commit 39ed9e7.

♻️ This comment has been updated with latest results.

[neringaalt]

Look carefully, there are more places that need to be updated