Bump pg from 1.5.6 to 1.5.7 (#256)

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

Author: dependabot[bot]

Gemfile.lock

@@ -394,7 +394,7 @@ GEM
     parser (3.3.4.0)
       ast (~> 2.4.1)
       racc
-    pg (1.5.6)
+    pg (1.5.7)
     plek (5.1.0)
     prometheus_exporter (2.1.0)
       webrick