Bump lance version to 5.0.0-beta.6 and arrow to 15.0.2

[SteveStevenpoor]

Bump lance version to 5.0.0-beta.6 and arrow to 15.0.2. This is the new lance API and corresponds to lance-spark connector.

[fightBoxing]

Thanks @SteveStevenpoor for kicking off the com.lancedb → org.lance migration — direction is correct and this unblocks #47 (the dependabot bump on the old coordinate).

Since this PR was opened in April, upstream lance has moved forward. Could you refresh the version pins?

Property	This PR	Suggested
lance.version	5.0.0-beta.6	7.0.0 (latest stable, 2026-05-27)
arrow.version	15.0.2	18.3.0 (matches lance 7.x; per lancedb/lance java/pom.xml)
junit.version	5.10.1	keep ✅

Reference: lance-format/lance-spark is already on org.lance:lance-core:7.0.0-rc.1 + arrow 18.3.0.

If there is no response within ~7 days, the project will refresh this in a follow-up PR with co-authored-by attribution to preserve the migration credit.

[github-actions]

ACTION NEEDED
Lance follows the Conventional Commits specification for release automation.

The PR title and description are used as the merge commit message. Please update your PR title and description to match the specification.

For details on the error please inspect the "PR Title Check" action.

[SteveStevenpoor]

Thanks @SteveStevenpoor for kicking off the com.lancedb → org.lance migration — direction is correct and this unblocks #47 (the dependabot bump on the old coordinate).

Since this PR was opened in April, upstream lance has moved forward. Could you refresh the version pins?
Property This PR Suggested
lance.version 5.0.0-beta.6 7.0.0 (latest stable, 2026-05-27)
arrow.version 15.0.2 18.3.0 (matches lance 7.x; per lancedb/lance java/pom.xml)
junit.version 5.10.1 keep ✅

Reference: lance-format/lance-spark is already on org.lance:lance-core:7.0.0-rc.1 + arrow 18.3.0.

If there is no response within ~7 days, the project will refresh this in a follow-up PR with co-authored-by attribution to preserve the migration credit.

Hi! I've updated the PR to use the requested versions.

Is it okay if I squash both commits into a single one and update the PR title with newer versions?