Console crashes when pinnedResources is null (which could be the case starting 4.13)

This is a clone of issue OCPBUGS-7764. The following is the description of the original issue:
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This is a clone of issue OCPBUGS-6831. The following is the description of the original issue:
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Description of problem:
The console crashes when it used with a user settings ConfigMap that is created with a 4.13+ console. This version saves "null" for the key "console.pinnedResources" which doesn't happen before and the old console version could not handle this well.

Version-Release number of selected component (if applicable):
4.8-4.12

How reproducible:
Always, but only in the edge case that someone used a newer console first and then downgraded.

This can happen only by manually applying the user settings ConfigMap or when downgrading a cluster.

Steps to Reproduce:
Open the user-settings ConfigMap and set "console.pinedResources" to "null" (with quotes as all ConfigMap values needs to be strings)

Or run this patch command:

oc patch -n openshift-console-user-settings configmaps user-settings-kubeadmin --type=merge --patch '{"data":{"console.pinnedResources":"null"}}'

Open console...

Actual results:
Console crashes

Expected results:
Console should not crash