v2index/sample shows empty list

[yangcao77]

/kind bug

Which area this bug is related to?

/area registry

What versions of software are you using?

Operating System:

Go Pkg Version:

Bug Summary

Describe the bug:

v2index/sample shows empty list

To Reproduce:

registry.devfile.io/v2index/samples

Expected behavior

should show samples index

Any logs, error output, screenshots etc? Provide the devfile that sees this bug, if applicable.

Additional context

Any workaround?

Suggestion on how to fix the bug

it is because maxSchemaVersion and minSchemaVersion filters are applied without checking if the two values are provided.
and in order to apply the filter, it needs to read the version list from the index. but the current extraDevfileEntries.yaml is still with the old index schema, and does not include the version list. In this case, we should still show the old index schema content.