Prepare morley-1.8.0

Description

Problem: recetly we removed all QuickCheck-related stuff from morley, so we want to make a new release to use a smaller morley in some projects.

Solution: since there are braking changes (e. g. this removal), we update the version to 1.8.0.

New release of lorentz seems to be unnecessary now, it will be made after UStore is moved out of it. indigo doesn't seem to have any essential changes since the last release.

Related issue(s)

None

✅ Checklist for your Merge Request

Related changes (conditional)

• Tests (see short guidelines)

  • If I added new functionality, I added tests covering it.
  • If I fixed a bug, I added a regression test to prevent the bug from silently reappearing again.

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    • Haddock
    • docs/
  • I updated changelog files of all affected packages released to Hackage if my changes are externally visible.

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