DDC-2151: [GH-515] Fixes sandbox cli: The helper "em" is not defined.

[doctrinebot]

Jira issue originally created by user @beberlei:

This issue is created automatically through a Github pull request on behalf of tranver:

Url: #515

Message:

In afd8ea9 $helpers became an instance of HelperSet and caused an "The helper "em" is not defined." exception.

[doctrinebot]

Issue was closed with resolution "Fixed"

[doctrinebot]

Comment created by @beberlei:

A related Github Pull-Request [GH-515] was closed
#515

[doctrinebot]

Comment created by @doctrinebot:

A related Github Pull-Request [GH-515] was closed:
doctrine/dbal#515