Label Selector only works with one key/value pair

[lizardruss]

What happened?
An error occurs when using more than one key/value pair as a label selector for port forwarding.

Error:
Unable to start portforwarding: Unable to list devspace pods: found ',', expected: !, identifier, or 'end of string'

Example Configuration:

ports:
- labelSelector:
    app: redis-ha
    redis-role: master
  portMappings:
  - localPort: 6379
    remotePort: 6379

What did you expect to happen instead?
I expected portforwarding to start and match the pod on multiple labels.

How can we reproduce the bug? (as minimally and precisely as possible)
Use multiple key/value pairs in a labelSelector and run devspace up. See "Example Configuration" above.

Local Environment:

• Operating System: mac
• Deployment method: helm

Kubernetes Cluster:

• Cloud Provider: local
• Kubernetes Version: [use kubectl version]

Client Version: version.Info{Major:"1", Minor:"9", GitVersion:"v1.9.2", GitCommit:"5fa2db2bd46ac79e5e00a4e6ed24191080aa463b", GitTreeState:"clean", BuildDate:"2018-01-18T21:12:46Z", GoVersion:"go1.9.2", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.5", GitCommit:"32ac1c9073b132b8ba18aa830f46b77dcceb0723", GitTreeState:"clean", BuildDate:"2018-06-21T11:34:22Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}

Anything else we need to know?
This occurred with the stable/redis-ha@2.2.3 chart. With that version of the chart, there are several nodes labeled as master or slave, but only the master pods can be written to. I've upgrade to the 3.0 version of the chart, which has a different deployment model, but this issue would occur with any pod that needs multiple labels to be uniquely identified.

/kind bug

[FabianKramm]

Thanks for opening this issue! Should be fixed with version v2.3.1