Travis.yml Bug with php 7.4.x

Hello community,

I have a small problem.

So I wrote an application following the laravel TDD forum series.

Now I run my testsuite with php unit .xml

result = no problem all tests pass

after this I wanted to set up my continuous testing with travis

unfortunately if I run the same tests with travis I am getting the following error

ErrorException: Trying to access array offset on value of type null

/home/travis/build/OfflineONE/Offline/vendor/laravel/telescope/src/Watchers/QueryWatcher.php:46

/home/travis/build/OfflineONE/Offline/vendor/laravel/framework/src/Illuminate/Events/Dispatcher.php:369

for reference

https://travis-ci.com/github/OfflineONE/Offline/builds/156130895

I tracked the issue down to the following Bug Issue

https://github.com/composer/composer/pull/8296

but a

composer self-update --snapshot 

doesn't help

I really don't know what to do now