Expose if runner can run sessions
It will be very helpful to know when we register a runner if it can run or not sessions. This would give us the option to filter them using this attribute.
In the Web IDE, in order to identify if the currently registered runners can or cannot run sessions we use a tag that the user has to configure in the runner. But, what if the user set that tag in a docker executor for example? (which can't at the moment run sessions). Using this new attribute, we could prevent some configuration errors, and ensure that the runner can indeed run the terminals.
Edited by Francisco Javier López (ex-Gitlab)