"egeloen/http-adapter" deprecated #484

Composer message:

Package egeloen/http-adapter is abandoned, you should avoid using it. Use php-http/httplug instead.

You should remove "egeloen/http-adapter" from require, and instead move it to require-dev.
This suffices for testing but allows people to use other not deprecated packages instead.
In general it is always a good idea to not directly include those proposed dependencies in require, but keep them in require-dev or suggest.