[release/9.0-staging] Avoid exception when parsing AD path for port number

[github-actions]

Backport of #109977 to release/9.0-staging

Fixes#109858

Customer Impact

• Customer reported

This is breaking existing users of Active Directory through System.DirectoryServices.AccountManagement although there appears to be a workaround.

Regression

• Yes
• No

Regression in v9 from #89787.

Testing

There is pending community testing.

This is an ActiveDirectory issue which is hard to test since it requires either local usage of AD or a setup of virtual machine(s) to test. There are no automated tests.

Risk

Low; even though the test has not yet been verified the change is to simply change from calling the constructor of the System.Uri class to using System.Uri.TryCreate().

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