Adds stream categories to dashboard widgets

[kingzacko1]

Description

Adds stream categories to Widgets so they can be scoped to stream categories. Offshoot PR of #20110.

/prd Graylog2/graylog-plugin-enterprise#8295 /nocl will be added to CL on main PR

Motivation and Context

https://github.com/Graylog2/graylog-plugin-enterprise/issues/7926

How Has This Been Tested?

Tested locally by manually adding stream_categories field to a MessagesWidget on a saved dashboard. Will continue testing other widgets.

Screenshots (if appropriate):

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Refactoring (non-breaking change)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [ ] My code follows the code style of this project.
• [ ] 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.