Updated code that validates managed_image_os_disk_snapshot_name and managed_image_data_disk_snapshot_prefix

[VladimirKhvostov]

Description

MyImage2025.01.01-snapshot is a perfectly valid snapshot name, but original code does not accept it. Original code does not allow to use dots in the snapshot name.

Rollback Plan

Changes to Security Controls

No

[hashicorp-cla-app]

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[hashicorp-cla-app]

Thank you for your submission! We require that all contributors sign our Contributor License Agreement ("CLA") before we can accept the contribution. Read and sign the agreement

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[JenGoldstrich]

Hey @VladimirKhvostov this change seems good to me, thank you for the unit test changes as well.

Can you please sign the CLA mentioned in the previous comment? Once that's done I will validate it quickly and then we should be good to merge this

[tanmay-hc]

@VladimirKhvostov Could you please sign the CLA so we can proceed with the PR?