Fix(core): fix relation declaration

[stonebuzz]

Checklist before requesting a review

Please delete options that are not relevant.

• I have performed a self-review of my code.
• I have added tests (when available) that prove my fix is effective or that my feature works.
• I have updated the CHANGELOG with a short functional description of the fix or new feature.
• This change requires a documentation update.

Description

• It fixes Invalid relations spam in log #524

When GLPI attempts to verify the relationship consistency, the generation of the item type (DBUTILS->getItemTypeForTable()) from the table is incorrect.

For example:
PluginOrderOtherType != PluginOrderOthertype

This discrepancy triggers an error.

However, GLPI is unable to correctly handle the uppercase "T".

I therefore propose renaming the classes by removing the final uppercase letter to resolve this issue.

Screenshots (if appropriate):