Bump reactive-graph-behaviour-model-api from 31eff9b to 61f9f97

Bumps [reactive-graph-behaviour-model-api](https://github.com/reactive-graph/reactive-graph) from `31eff9b` to `61f9f97`.
- [Release notes](https://github.com/reactive-graph/reactive-graph/releases)
- [Commits](reactive-graph/reactive-graph@31eff9b...61f9f97)

---
updated-dependencies:
- dependency-name: reactive-graph-behaviour-model-api
  dependency-version: 61f9f9769f54df4b027e3ca670f1b7a68b655a24
  dependency-type: direct:production
...

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Author: dependabot[bot]