feat: add tnightengale:dbt_activity_schema to hub.json

[tnightengale]

Description

A dbt-Core package for generating models from an activity stream.

Link to your package's repository: https://github.com/tnightengale/dbt-activity-schema

Checklist

This checklist is a cut down version of the best practices that we have identified as the package hub has grown. Although meeting these checklist items is not a prerequisite to being added to the Hub, we have found that packages which don't conform provide a worse user experience.

First run experience

• [x] The package includes a README which explains how to get started with the package and customise its behaviour
• [x] The README indicates which data warehouses/platforms are expected to work with this package

Customisability

• [x] The package uses ref or source, instead of hard-coding table references.

  Packages for data transformation (delete if not relevant):

• [x] provide a mechanism (such as variables) to customise the location of source tables.
• [x] do not assume database/schema names in sources.

Dependencies

Dependencies on dbt Core

• [x] The package has set a supported require-dbt-version range in dbt_project.yml. Example: A package which depends on functionality added in dbt Core 1.2 should set its require-dbt-version property to [">=1.2.0", "<2.0.0"].

  Dependencies on other packages defined in packages.yml:

• [x] Dependencies are imported from the dbt Package Hub when available, as opposed to a git installation.
• [x] Dependencies contain the widest possible range of supported versions, to minimise issues in dependency resolution.
• [x] In particular, dependencies are not pinned to a patch version unless there is a known incompatibility.

  Interoperability

• [x] The package does not override dbt Core behaviour in such a way as to impact other dbt resources (models, tests, etc) not provided by the package.
• [x] The package uses the cross-database macros built into dbt Core where available, such as {{ dbt.except() }} and {{ dbt.type_string() }}.
• [x] The package disambiguates its resource names to avoid clashes with nodes that are likely to already exist in a project. For example, packages should not provide a model simply called users.

Versioning

• [x] (Required): The package's git tags validates against the regex defined in version.py
• [x] The package's version follows the guidance of Semantic Versioning 2.0.0. (Note in particular the recommendation for production-ready packages to be version 1.0.0 or above)