chore(main): release 6.68.0

[release-please[bot]]

:robot: I have created a release beep boop

6.68.0 (2024-05-27)

Features

• [java] allow passing libraries_bom_version from env (#1967) (#3112) (7d5a52c)
• Allow DML batches in transactions to execute analyzeUpdate (#3114) (dee7cda)
• spanner: Add support for Proto Columns in Connection API (#3123) (7e7c814)

Bug Fixes

• Allow getMetadata() calls before calling next() (#3111) (39902c3)

Dependencies

• Update dependency org.graalvm.buildtools:native-maven-plugin to v0.10.2 (#3117) (ddebbbb)

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[release-please[bot]]

:robot: Release is at https://github.com/googleapis/java-spanner/releases/tag/v6.68.0 :sunflower:

[release-trigger[bot]]

Triggered job: cloud-devrel/client-libraries/java/java-spanner/release/stage (2024-05-27T10:47:19.050Z)

To trigger again, remove the autorelease: triggered label (in a few minutes).

[release-tool-publish-reporter[bot]]

The release build has started, the log can be viewed here. :sunflower:

[release-tool-publish-reporter[bot]]

:egg: You hatched a release! The release build finished successfully! :purple_heart: