Bump used `formatting` package version

Description

Problem: there was a bug in formatting package that caused 0 :: Word to be printed as -0. This has been fixed recently by the new maintainer of this package, but the new releases are not yet in LTS.

Solution: include a new version manually to stack.yaml.

Related issue(s)

Resolves 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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