Update cicd-keyvault.md to fix variables

[LuKePicci]

Added missing AzureKeyVaultTenantId variable Renamed AzureKeyVaultName variable into AzureKeyVaultCertificateName

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

Learn Build status updates of commit 2067054:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
msix-src/desktop/cicd-keyvault.md	:white_check_mark:Succeeded

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