Update to ERB 6.0.0. (#309)

Author: conradwt

Gemfile.lock

@@ -99,7 +99,7 @@ GEM
     dotenv (3.1.8)
     drb (2.2.3)
     ed25519 (1.4.0)
-    erb (5.1.3)
+    erb (6.0.0)
     erubi (1.13.1)
     et-orbi (1.4.0)
       tzinfo