fix consul rails 5.2 enabling logic

so it's actually enabled with a 'true' value

Change-Id: Ib35669b69880dbf7059fee6eda49fdfc2aaa9314
Reviewed-on: https://gerrit.instructure.com/199344
Reviewed-by: Rob Orton <rob@instructure.com>
QA-Review: Rob Orton <rob@instructure.com>
Product-Review: Rob Orton <rob@instructure.com>
Tested-by: Jenkins

config/canvas_rails5.rb

@@ -46,7 +46,7 @@ unless defined?(CANVAS_RAILS5_1)
         result = nil unless result.is_a?(Net::HTTPSuccess)
         break if result
       end
-      CANVAS_RAILS5_1 = !(result && Base64.decode64(JSON.load(result.body).first['Value']) == 'false')
+      CANVAS_RAILS5_1 = !(result && Base64.decode64(JSON.load(result.body).first['Value']) == 'true')
     rescue
       CANVAS_RAILS5_1 = true
     end