Merge pull request #983 from dxw/renovate/mini_racer-0.x-lockfile

Update dependency mini_racer to v0.19.1

Author: renovate[bot]

Gemfile.lock

@@ -191,7 +191,7 @@ GEM
     matrix (0.4.2)
     method_source (1.1.0)
     mini_mime (1.1.5)
-    mini_racer (0.19.0)
+    mini_racer (0.19.1)
       libv8-node (~> 24.1.0.0)
     minitest (5.25.5)
     msgpack (1.8.0)