Bump pg from 1.1.2 to 1.1.3

Bumps [pg](https://bitbucket.org/ged/ruby-pg) from 1.1.2 to 1.1.3.
- [Changelog](https://bitbucket.org/ged/ruby-pg/src/master/History.rdoc)
- [Commits](https://bitbucket.org/ged/ruby-pg/branches/compare/v1.1.3..v1.1.2)

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

Gemfile.lock

@@ -141,7 +141,7 @@ GEM
       hashery (~> 2.0)
       ruby-rc4
       ttfunk
-    pg (1.1.2)
+    pg (1.1.3)
     powerpack (0.1.2)
     pry (0.11.3)
       coderay (~> 1.1.0)