chore(main): release 1.6.0

[release-please[bot]]

:robot: I have created a release beep boop

1.6.0 (2023-04-26)

Features

• Enable instance-level connection (#316) (9af8e86)

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[release-please[bot]]

:robot: Release is at https://github.com/googleapis/python-spanner-sqlalchemy/releases/tag/v1.6.0 :sunflower:

[release-trigger[bot]]

Triggered job: cloud-devrel/client-libraries/python/googleapis/python-spanner-sqlalchemy/release/release (2023-04-27T11:37:51.643Z)

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: