Bump pghero from 3.3.3 to 3.3.4

Bumps [pghero](https://github.com/ankane/pghero) from 3.3.3 to 3.3.4.
- [Changelog](https://github.com/ankane/pghero/blob/master/CHANGELOG.md)
- [Commits](https://github.com/ankane/pghero/compare/v3.3.3...v3.3.4)

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

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile.lock

@@ -253,7 +253,7 @@ GEM
     mini_magick (4.12.0)
     mini_mime (1.1.5)
     mini_portile2 (2.8.4)
-    minitest (5.19.0)
+    minitest (5.20.0)
     msgpack (1.6.0)
     multi_json (1.15.0)
     multi_xml (0.6.0)
@@ -283,7 +283,7 @@ GEM
       ast (~> 2.4.1)
       racc
     pg (1.5.4)
-    pghero (3.3.3)
+    pghero (3.3.4)
       activerecord (>= 6)
     prometheus-client (4.2.1)
     public_suffix (5.0.1)