[browser] more cancelation tests

[pavelsavara]

From here #80257 (comment)

• Would it be useful add a short delay before the Cancel, to give a chance for ImportAsync get started?
• Also, would it be useful to have another test that tries to import from an external url?
• What about a test for importing a non-existent file - like ./non-existent.js, and a url https://www.foobar.com/non-existent.js, and canceling for those?

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Issue Details

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From here #80257 (comment)

• Would it be useful add a short delay before the Cancel, to give a chance for ImportAsync get started?
• Also, would it be useful to have another test that tries to import from an external url?
• What about a test for importing a non-existent file - like ./non-existent.js, and a url https://www.foobar.com/non-existent.js, and canceling for those?

Author:	pavelsavara
Assignees:	-
Labels:	arch-wasm, area-System.Runtime.InteropServices.JavaScript
Milestone:	Future

[pavelsavara]

related to
src\libraries\System.Net.WebSockets.Client\tests\CancelTest.cs
src\libraries\System.Net.WebSockets.Client\tests\AbortTest.cs