AMBASSADOR_SINGLE_NAMESPACE should be true/false not set/unset

[ryandawsonuk]

If you set the env var AMBASSADOR_SINGLE_NAMESPACE to false, ambassador still only watches resources in that namespace. If you don't set the env var at all, then it watches all namespaces.

This has been noted before - #588 (comment)

I believe it is because of https://github.com/datawire/ambassador/blob/335e58e440fd81693310d84e370e576be8d96655/ambassador/kubewatch.py#L28 , which isn't doing a check on the value - https://stackoverflow.com/a/30015489

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[ryandawsonuk]

This is less important now helm/charts#12670 is merged as it can now easily be set or not set via a parameter in the helm chart

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.