Bump verif/core-v-verif from 6779193 to 18c9d28

Bumps [verif/core-v-verif](https://github.com/openhwgroup/core-v-verif) from `6779193` to `18c9d28`.
- [Release notes](https://github.com/openhwgroup/core-v-verif/releases)
- [Commits](openhwgroup/core-v-verif@6779193...18c9d28)

---
updated-dependencies:
- dependency-name: verif/core-v-verif
  dependency-type: direct:production
...

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