Bump pghero from 2.8.1 to 2.8.2 (#15804)

Bumps [pghero](https://github.com/ankane/pghero) from 2.8.1 to 2.8.2.
- [Release notes](https://github.com/ankane/pghero/releases)
- [Changelog](https://github.com/ankane/pghero/blob/master/CHANGELOG.md)
- [Commits](https://github.com/ankane/pghero/compare/v2.8.1...v2.8.2)

---
updated-dependencies:
- dependency-name: pghero
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile.lock

@@ -556,7 +556,7 @@ GEM
     pg_search (2.3.5)
       activerecord (>= 5.2)
       activesupport (>= 5.2)
-    pghero (2.8.1)
+    pghero (2.8.2)
       activerecord (>= 5)
     pry (0.14.1)
       coderay (~> 1.1)