Fix a typo

Author: jbranchaud

README.md

@@ -551,7 +551,7 @@ _877 TILs and counting..._
 - [Show Pending Migrations](rails/show-pending-migrations.md)
 - [Show Rails Models With Pry](rails/show-rails-models-with-pry.md)
 - [Show Rails Routes With Pry](rails/show-rails-routes-with-pry.md)
-- [Test If An Instance Variable Assigned](rails/test-if-an-instance-variable-was-assigned.md)
+- [Test If An Instance Variable Was Assigned](rails/test-if-an-instance-variable-was-assigned.md)
 - [Truncate Almost All Tables](rails/truncate-almost-all-tables.md)
 - [Update Column Versus Update Attribute](rails/update-column-versus-update-attribute.md)
 - [Where Am I In The Partial Iteration?](rails/where-am-i-in-the-partial-iteration.md)