dev access key in the "install-web-dir" command

[aschempp]

Removes storing the dev access key in the install-web-dir command, where it actually never should have been. In the previous implementation the access key was stored multiple times (in manager config and in .env file). It also meant that removing the key through the command would re-add it the next time the command is run without arguments (because the manager config still exists). This is now all fixes by simply updating the .env file through the API.

[aschempp]

The changes in ContaoKernel are not unrelated, they update the manager-bundle to match the manager-plugin. The original title and description never sayed this is only to add new API commands 😉

[leofeyer]

Thank you @aschempp.