increase timeout on ZeroByteRead_IssuesZeroByteReadOnUnderlyingStream test

[wfurt]

fixes#67509

I saw occasional local failures on my Win11 machine. I did not see failure since I increased the timeout.
Not that PassingTestTimeoutMilliseconds is 60s for HTTP. I could possibly use that instead but the 30s is holding so far for me.

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Issue Details

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fixes #67509

I saw occasional local failures on my Win11 machine. I did not see failure since I increased the timeout.
Not that PassingTestTimeoutMilliseconds is 60s for HTTP. I could possibly use that instead but the 30s is holding so far for me.

Author:	wfurt
Assignees:	wfurt
Labels:	area-System.Net.Http
Milestone:	7.0.0

[stephentoub]

Not that PassingTestTimeoutMilliseconds is 60s for HTTP. I could possibly use that instead but the 30s is holding so far for me.

There's little harm in using a longer timeout... it's only problematoc when the test fails. My preference would be to just use the existing named constant.

[karelz]

@stephentoub can you please approve? (assuming it is now ok) Thanks!