Bump firrtl from `c00c0f3` to `69b8a88` (#281)

Bumps [firrtl](https://github.com/freechipsproject/firrtl) from `c00c0f3` to `69b8a88`.
- [Release notes](https://github.com/freechipsproject/firrtl/releases)
- [Commits](https://github.com/freechipsproject/firrtl/compare/c00c0f3ad77f003edeea0c8cdd8c818f5f649d76...69b8a88553247714ac82a778ed80c9a2f3491af9

)

---
updated-dependencies:
- dependency-name: firrtl
  dependency-type: direct:production
...

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