fix(event log) : export as csv

Description

** This PR fixes logs export issue on event log page

Fixes # MON-15404

[x] Patch fixing an issue (non-breaking change)
[ ] New functionality (non-breaking change)
[ ] Breaking change (patch or feature) that might cause side effects breaking part of the Software

On the event log page click on ''export as csv'' button. A generated file should contain all event logs

[x] I have followed the coding style guidelines provided by Centreon
[x] I have commented my code, especially new classes, functions or any legacy code modified. (docblock)
[x] I have commented my code, especially hard-to-understand areas of the PR.
[x] I have rebased my development branch on the base branch (master, maintenance).