@shanzhai/serial-step 
A Shanzhai build step which runs any number of child build steps in serial.
Usage
Within a trigger's event handler, return an instance of SerialStep similar to
the following:
new SerialStep(
`A description of the operation being performed`,
[
new FirstStepToExecute(),
new SecondStepToExecute(),
new ThirdStepToExecute(),
]
)This will execute each of the steps sequentially; one after the other.
Dependencies
This package has no runtime dependencies.
Peer Dependencies
This package has no runtime peer dependencies (it does not expect any other packages to be installed alongside itself).
