[!!!][TASK] Set Sys log dateformat to system default

[DavidsWONG]

TYPO3 configuration knows a global date format configuration
within the installation tool. See TYPO3_CONF_VARS/SYS/ddmmyy

Use this global format as the default for Sys log

TYPO3_CONF_VARS/SYS/ddmmyy is more efficient than
TYPO3_CONF_VARS/SYS/USdateFormat
ddmmyy ( Y-M-D | M-D-Y | D-M-Y)
USdateFormat ( M-D-Y | D-M-Y)

[TYPO3IncTeam]

Thank you for your contribution to TYPO3. We are using Gerrit Code Review for our contributions and took the liberty to convert your pull request to a review in our review system.
You can find your patch at: https://review.typo3.org/c/Packages/TYPO3.CMS/+/65235
For further information on how to contribute have a look at https://docs.typo3.org/typo3cms/ContributionWorkflowGuide/