chore(main): release appengine 0.7.0

[release-please[bot]]

:robot: I have created a release beep boop

0.7.0 (2022-04-22)

Features

• add gcs log dir option

• Replace the appengine exec class with an alias to serverless-exec

• Update stackdriver dependency

  Bug Fixes

• Fix exception when a shell command rather than a command array is given in Exec

• Fix failure in the appengine:exec cloud_build strategy when App Engine doesn't provide the image

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[release-please[bot]]

:robot: Release is at https://github.com/GoogleCloudPlatform/appengine-ruby/releases/tag/appengine/v0.7.0 :sunflower:

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

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

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