chore: update accelerator-toolbox requirement

Updates the requirements on [accelerator-toolbox](https://github.com/atcollab/at) to permit the latest version.

Updates `accelerator-toolbox` to 0.7.1
- [Release notes](https://github.com/atcollab/at/releases)
- [Commits](atcollab/at@pyat-0.2.0...pyat-0.7.1)

---
updated-dependencies:
- dependency-name: accelerator-toolbox
  dependency-version: 0.7.1
  dependency-type: direct:production
  dependency-group: dev-dependencies
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

pyproject.toml

@@ -16,7 +16,7 @@ dependencies = [
     "numpy",
     "scipy",
     "pytac>=0.3.0",
-    "accelerator-toolbox (>=0.2.0,<0.7.1)",
+    "accelerator-toolbox (>=0.2.0,<0.7.2)",
     "cothread",
     "softioc",
 ]