Merge pull request #349 from ruby-i18n/dependabot/bundler/psych-5.3.1

Bump psych from 5.2.6 to 5.3.1

Author: movermeyer

Gemfile.lock

@@ -8,7 +8,7 @@ GEM
     builder (3.3.0)
     coderay (1.1.3)
     concurrent-ruby (1.3.5)
-    date (3.5.0)
+    date (3.5.1)
     debug (1.11.0)
       irb (~> 1.10)
       reline (>= 0.3.8)
@@ -93,7 +93,7 @@ GEM
       method_source (~> 1.0)
     pry-nav (1.0.0)
       pry (>= 0.9.10, < 0.15)
-    psych (5.2.6)
+    psych (5.3.1)
       date
       stringio
     racc (1.8.1)
@@ -133,7 +133,7 @@ GEM
     ruby-progressbar (1.13.0)
     rubyzip (3.2.2)
     semver2 (3.4.2)
-    stringio (3.1.7)
+    stringio (3.2.0)
     test-unit (3.7.1)
       power_assert
     thor (1.4.0)