build(deps): bump pg from 1.5.7 to 1.5.9 (#4967)

Bumps [pg](https://github.com/ged/ruby-pg) from 1.5.7 to 1.5.9.
- [Changelog](https://github.com/ged/ruby-pg/blob/master/History.md)
- [Commits](ged/ruby-pg@v1.5.7...v1.5.9)

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

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

Author: dependabot[bot]

Gemfile

@@ -10,7 +10,7 @@ end
 # User management and login workflow.
 gem "devise", '>= 4.7.1'
 # Postgres database adapter.
-gem "pg", "~> 1.5.7"
+gem "pg", "~> 1.5.9"
 # Web server.
 gem "puma"
 # Rails web framework.

Gemfile.lock

@@ -458,7 +458,7 @@ GEM
       hashery (~> 2.0)
       ruby-rc4
       ttfunk
-    pg (1.5.7)
+    pg (1.5.9)
     popper_js (2.11.8)
     prawn (2.5.0)
       matrix (~> 0.4)
@@ -789,7 +789,7 @@ DEPENDENCIES
   orderly (~> 0.1)
   paper_trail
   pdf-reader
-  pg (~> 1.5.7)
+  pg (~> 1.5.9)
   prawn-rails
   pry-doc
   pry-nav