Migrations: Set a long timeout by default on the migration of system dates (closes #21013)

[AndyButland]

Prerequisites

• I have added steps to test this contribution in the description below

Addresses #21013

Description

Although as noted in the discussion on the linked issue we can resolve this by configuring a command timeout in the connection string, it makes sense to use a long one by default for these migration queries.

So this PR will set a timeout of 5 minutes unless a longer one is already configured.

Testing

Use a SQL update like the following to re-run the migration and verify with a breakpoint that the CommandTimeout is set as expected.

update umbracoKeyValue
set value = '{EB1E50B7-CD5E-4B6B-B307-36237DD2C506}'
where [key] = 'Umbraco.Core.Upgrader.State+Umbraco.Core'

If set in the connection string to a value longer than 300 seconds, e.g. with the following, then the configured value should be kept:

"umbracoDbDSN": "Server=.\\SQLEXPRESS;Database=UmbracoCms17;Integrated Security=true;TrustServerCertificate=true;Connect Timeout=500"

[Copilot]

Pull request overview

This PR adds a default command timeout of 5 minutes (300 seconds) to the system dates UTC migration to prevent timeout issues on databases with large tables. The migration updates numerous date columns across multiple tables, which can be time-consuming on production databases with significant data volumes.

• Sets CommandTimeout to 300 seconds for the MigrateSystemDatesToUtc migration
• Preserves any existing longer timeout configured via connection string
• Addresses issue #21013 where migrations were timing out on large databases

[kjac]

👍

[kjac]

👍