Mention outcome.force_result() and add link to pluggy's docs
Mention outcome.force_result() and add link to pluggy's docs

Related to #3169

pytest-dev/pytest,ddboline/pytest,alfredodeza/pytest,tareqalayan/pytest,nicoddemus/pytest,hackebrot/pytest,markshao/pytest,tomviner/pytest,The-Compiler/pytest,txomon/pytest,tomviner/pytest,nicoddemus/pytest,Akasurde/pytest,RonnyPfannschmidt/pytest,davidszotten/pytest,The-Compiler/pytest,pfctdayelise/pytest