Dont check for update if FormatTools.VERSION is "(unknown version)"

[CGDogan]

Sometimes version string is unknown version https://github.com/ome/bioformats/blob/e1aaf58bee6eebe5d4fd425e2005565d42890af7/components/formats-api/src/loci/formats/FormatTools.java#L290 . in this case, print a debug log statement here https://github.com/ome/bioformats/blob/e1aaf58bee6eebe5d4fd425e2005565d42890af7/components/formats-bsd/src/loci/formats/UpgradeChecker.java#L211-L211 that cannot check update because dont know version and don't make a request that will otherwise fail and print a verbose error

[sbesson]

On the principle, I agree the upgrade checker could handle the cases where FormatTools.VERSION is set to its fallback value and return early for instance.

Trying to understand the context, can you elaborate on the scenario you are trying to address here? FormatTools.VERSION should only be set to (unknown version) if the metadata cannot be found in the JAR manifest and should never happen with release versions.

[CGDogan]

Sorry I was indeed referring to development versions - it would help save bandwidth but as you said I have never seen it happen with release versions. So this is a really, really minor issue.