Update composer.json

[Alizee-Me]

In order to make it compatible with php8

[Alexandre-T]

Thanks for your PR. Could you please add PHP8 in the matrice of travis test?

[Alizee-Me]

Thanks for your PR. Could you please add PHP8 in the matrice of travis test?

Done in Add php 8.0 in travis test #15

Is it enough ?

[Alexandre-T]

Unfortunately, it isn't enough. The tools used to test this bundle cannot be used with PHP8. So all test are failing. I tried to update it, a few weeks ago, but I have two problems. First, the last version of the library PHPCas has some bugs during session creation. I think that I can avoid this problem by fixing the version of library. Second one, I have to replace one of the tools.

If you need it immediately, you can call your patch in composer.
If you can wait some days, I will create a dev version with PHP8 without warranty.
In a few months, I will fix all these test and I will be publish a new release.

But currently, I have too much work to do it.