Merged PR 360: 2523 - Logging Rewards updates.

## Summary
This PR updates `PrimaiteGymEnv` and `PrimaiteRayMARLEnv` within `environment.py` to log reward values per step and per episode.
Corrects an import statement within `io.py` - removing the use of `src`.
Fixes an error within notebooks that saw them failing following a rename of `game_config` to `env_config`.

## Test process
 - Tests all continue to pass, and notebooks now run without error. This PR does not change any functionality, just adds some logging.
 - Searched for the catch-22 that would trip me up as part of this ticket. A 3 line change felt like too simple an implementation...

## Checklist
- [X] PR is linked to a **work item**
- [X] **acceptance criteria** of linked ticket are met
- [X] performed **self-review** of the code
- [ ] 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
- [X] updated the **change log**
- [X] ran **pre-commit** checks for code style
- [X] attended to any **TO-DOs** left in the code

Related work items: #2523

CHANGELOG.md

@@ -20,6 +20,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added the ability for a DatabaseService to terminate a connection.
 - Added active_connection to DatabaseClientConnection so that if the connection is terminated active_connection is set to False and the object can no longer be used.
 - Added additional show functions to enable connection inspection.
+- Updates to agent logging, to include the reward both per step and per episode.
 
 
 ## [Unreleased]