Replace every instance of a variable with another variable

We can check the usage of a variable in workflow actions, but we can not replace every that variable with a different variable. To do so, we have to replace each instance of variable use one at a time.

Mass replacement of variables will save customers time and improve overall user experience. This feature should leverage the existing variable usage functionality to allow a user to replace all instance of a variable with another variable. Users should also be allowed to remove every instance of a variable.