Fix Azure Graph Service endpoint used for IP checking

[MattGal]

(continuation from https://github.com/dotnet/core-eng/issues/13691)

To double check:

• The right tests are in and and the right validation has happened. Guidance: https://github.com/dotnet/core-eng/tree/master/Documentation/Validation (just improves diagnosability of -ci specifying builds by logging their effective IP as seem by the Azure Graph Service)

[ghost]

Hello @MattGal!

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[MattGal]

Looks like some backup happening on the Apple TV queues, in the interest of not occupying them further I'm going to bypass policy here.