Add psgallery folder to store build artifacts

[KenitoInc]

[learn-build-service-prod[bot]]

Learn Build status updates of commit de73e17:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
.azure-pipelines/ci-build-migrate.yml	:white_check_mark:Succeeded

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[KenitoInc]

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