support podman by treating empty docker health check as healthy

[nougad]

Podman will include the Health dict even if no health check is defined for the container (see
containers/podman#20029).

This makes the check in uptime-kuma stuck in Pending

Fixes #3767

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Description

Fixes #3767

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings
• My code needed automated testing. I have added them (this is optional task)

Screenshots (if any)

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[CommanderStorm]

How does this affect docker?

[nougad]

If a container has no healthcheck defined, docker will return State.Health as an empty dict. If an healthcheck is defined the field State.Health.Status is one of starting, healthy or unhealthy. Both is covered with the existing check.

The patch treats on top of the existing healthy string also an empty string as healthy. It will not affect docker because for docker the Status field should never be empty.

[nougad]

closing this PR in favor of #4372