DDC-3689: [GH-1382] Patch second level cache association hydration

[doctrinebot]

Jira issue originally created by user @doctrinebot:

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

Url: #1382

Message:

Fixed incorrect use of keys in DefaultRegion::getMultiple() and simplified overall mechanism

[doctrinebot]

• is referenced by DDC-3687: Entities part of a hierarchy seem not to inherit SLC configuration from 'root' Entity

[doctrinebot]

Comment created by @doctrinebot:

A related Github Pull-Request [GH-1382] was labeled:
#1382

[doctrinebot]

Comment created by @doctrinebot:

A related Github Pull-Request [GH-1382] was assigned:
#1382

[doctrinebot]

Comment created by @doctrinebot:

A related Github Pull-Request [GH-1382] was merged:
#1382

[doctrinebot]

Issue was closed with resolution "Fixed"

[doctrinebot]

Comment created by @guilhermeblanco:

Master: 5f18618
2.5: 3e6c6af

[doctrinebot]

Comment created by @doctrinebot:

A related Github Pull-Request [GH-1382] was unassigned:
#1382

[doctrinebot]

Comment created by @doctrinebot:

A related Github Pull-Request [GH-1382] was assigned:
#1382