Add possibility to modify default action when hitting call buton to 'work number'
To support migrations comming from a traditional PBX like e.g. Cisco, it should be possible to make Teams call the 'work phone number' (=value in the AD attribute 'telephonNumber') by default when hitting the 'call' button. For a bigger number of users, you don't want to migrate everyone at the same time. So in this situation, you don't want to explain to everyone they should look up the phone number and enter this in the numpad instead of clicking the 'call' button. This is an issue when migrated users are calling to non-migrated users who mostly don't have a headset and/or aren't please to have and a headset and an old PBX-endpoint device like a Cisco phone. After the migration, this setting can be rolled back then.