build(deps): bump doctrine/orm from 3.0.1 to 3.1.2

Bumps [doctrine/orm](https://github.com/doctrine/orm) from 3.0.1 to 3.1.2.
- [Release notes](https://github.com/doctrine/orm/releases)
- [Commits](doctrine/orm@3.0.1...3.1.2)

---
updated-dependencies:
- dependency-name: doctrine/orm
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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