## Summary
This PR implements an "ActionPenalty" Reward class, that can be used for penalising an agent when it carries out an action other than DONOTHING.
The value for this can be configured within the scenario YAML file.
## Test process
I've written unit tests to check that the action penalty is correctly calculated and applied, another to check that the config is read correctly and loads into PrimaiteGymEnv correctly.
## Checklist
- [X] PR is linked to a **work item**
- [X] **acceptance criteria** of linked ticket are met
- [X] performed **self-review** of the code
- [X] written **tests** for any new functionality added with this PR
- [ ] updated the **documentation** if this PR changes or adds functionality
- [ ] written/updated **design docs** if this PR implements new functionality
- [ ] updated the **change log**
- [X] ran **pre-commit** checks for code style
- [ ] attended to any **TO-DOs** left in the code
Related work items: #2656
96f62a3229