[BUGFIX] Linkvalidator: Fix exception when validating external links

Provide an instance of \GuzzleHttp\Cookie\CookieJar for the 'cookies'
option when validating an external link, the previous value of true
resulted in an exception.

Releases: master
Resolves: #76631
Change-Id: I0a9089ff1a442783b4484cf1d512adb520d95dca
Reviewed-on: https://review.typo3.org/48577


Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Joerg Boesche <typo3@joergboesche.de>
Tested-by: Joerg Boesche <typo3@joergboesche.de>
Reviewed-by: Susanne Moog <typo3@susannemoog.de>
Tested-by: Susanne Moog <typo3@susannemoog.de>