Bump pg from 0.21.0 to 1.0.0

Bumps [pg](https://github.com/ged/ruby-pg) from 0.21.0 to 1.0.0.
- [Release notes](https://github.com/ged/ruby-pg/releases)
- [Changelog](https://github.com/ged/ruby-pg/blob/master/History.rdoc)
- [Commits](https://github.com/ged/ruby-pg/compare/v0.21.0...v1.0.0)

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

Gemfile.lock

@@ -411,7 +411,7 @@ GEM
       activerecord (>= 4.0, < 6.1)
     parser (2.7.1.4)
       ast (~> 2.4.1)
-    pg (0.21.0)
+    pg (1.0.0)
     pg_search (2.3.0)
       activerecord (>= 4.2)
       activesupport (>= 4.2)
@@ -691,7 +691,7 @@ DEPENDENCIES
   omniauth-twitter (~> 1.4.0)
   paperclip (~> 6.1.0)
   paranoia (~> 2.4.2)
-  pg (~> 0.21.0)
+  pg (~> 1.0.0)
   pg_search (~> 2.3.0)
   puma (~> 4.3.6)
   rails (= 5.1.7)