chore(main): release spanner 8.8.0

[codyoss]

🤖 I have created a release beep boop

8.8.0 (2026-06-24)

Features

• spanner: isolation_level and read_lock_mode are added to message .google.spanner.v1.CommitResponse (4715de9)
• spanner: Add cache updates API (#8124) (4715de9)
• spanner: Add cache updates API (#8307) (f1d31f9)
• spanner: Optimize replaceProjectIdToken from projectify (#8412) (28b6350)
• spanner: Optimize RequestId propagation and minimize OpenTelemetry active tracing overhead (#8329) (a59dde9)

Bug Fixes

• deps: Remove vulnerable dependency uuid (#8120) (3ec901e)
• spanner: Avoid overriding host context manager and isolate session creation context (#8441) (2a7c79f)
• spanner: Isolate OpenTelemetry background timers in ROOT_CONTEXT to prevent context and memory leaks (#8399) (f9e1102)
• spanner: Resolve prelint, eslint, and prettier CI build failures (#8359) (600ccca)
• Specify explicit destinations in spanner owlbot.py (#8304) (f81f0a6)

Performance Improvements

• spanner: Optimize query result decoding (#8452) (6ab8de0)
• spanner: Precompute common headers (#8451) (894cd8d)

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This PR was generated with Release Please. See documentation.

[gemini-code-assist]

Code Review

This pull request updates the @google-cloud/spanner package version from 8.7.1 to 8.8.0. The changes include updates to the release manifest, package.json, and the changelog, which documents new features such as the addition of isolation_level and read_lock_mode to CommitResponse, a new cache updates API, and a bug fix for owlbot.py destinations. I have no feedback to provide as there were no review comments.

[shivanee-p]

This release contains a reverted PR

[release-please]

🤖 Created releases:

• spanner-v8.8.0

🌻