Can a parent pipeline access the output-variables from a child pipeline

[dparr]

Is it possible for a parent pipeline run, that spawns a child pipeline, to access the `output-variable` from the child pipeline?

e.g. Running something like this, where the parent pipeline echos the value of $ec2Status in the child?:
```

image: atlassian/default-image:3

steps:

dummy-retrain:

- step: &dummy-retrain

name: Dummy retrain

script:

- echo "retrainOut = daves_value" >> $BITBUCKET_PIPELINES_VARIABLES_PATH

output-variables:

- retrainOut

dummy-register:

- step: &dummy-register

name: Dummy register

condition:

state: (retrainOut == "daves_value" || retrainOut == "bitbuckets_value" || retrainOut == "users_value")

script:

- echo $retrainOut

dummy-ec2-up:

- step: &dummy-ec2-up

name: Dummy EC2 up

script:

- echo "Starting EC2 instance..."

- echo "ec2Status=running" >> $BITBUCKET_PIPELINES_VARIABLES_PATH

output-variables:

- ec2Status

dummy-ec2-down:

- step: &dummy-ec2-down

name: Dummy EC2 down

script:

- echo "Stopping EC2 instance..."

- echo "ec2Status=stopped" >> $BITBUCKET_PIPELINES_VARIABLES_PATH

output-variables:

- ec2Status

dummy-ec2-status-report:

- step: &dummy-ec2-status-report

name: Dummy EC2 status report

script:

- echo $ec2Status

pipelines:

custom:

ec2-retrain-workflow:

- step: *dummy-ec2-up

- step: *dummy-retrain

- step: *dummy-ec2-down

default:

- step:

name: "Run EC2 retrain workflow"

type: pipeline

custom: ec2-retrain-workflow

- step: *dummy-ec2-status-report

- step: *dummy-register
```