DDC-2508: [GH-699] commented a change that was ahead of stable; added calls to getters

[doctrinebot]

Jira issue originally created by user @doctrinebot:

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

Url: #699

Message:

CreateHelperSet appears to be a method in 2.4, which is not stable yet and does not correspond with this 2.3 tutorial.
list_bugs.php was trying to get protected vars.

[doctrinebot]

Comment created by @doctrinebot:

A related Github Pull-Request [GH-699] was closed:
#699

[doctrinebot]

Issue was closed with resolution "Invalid"

[doctrinebot]

Comment created by @doctrinebot:

A related Github Pull-Request [GH-699] was assigned:
doctrine/dbal#699

[doctrinebot]

Comment created by @doctrinebot:

A related Github Pull-Request [GH-699] was closed:
doctrine/dbal#699