build(deps): bump deps/build/addonfactory_test_matrix_splunk

Bumps [deps/build/addonfactory_test_matrix_splunk](https://github.com/splunk/addonfactory_test_matrix_splunk) from `9d7a9d5` to `53bb287`.
- [Release notes](https://github.com/splunk/addonfactory_test_matrix_splunk/releases)
- [Commits](splunk/addonfactory_test_matrix_splunk@9d7a9d5...53bb287)

---
updated-dependencies:
- dependency-name: deps/build/addonfactory_test_matrix_splunk
  dependency-type: direct:production
...

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Author: dependabot[bot]