Don't throw exception when trying to resolve a possible link path

[daxian-dbw]

PR Summary

Fix #16293
Before #16165, we were using InternalSymbolicLinkLinkCodeMethods.WinInternalGetTarget to try resolving a possible link path, and that API never throws -- catch exception and returns null. However, File.ResolveLinkTarget throws when there is any error while resolving the link path, e.g. the file system doesn't support reparse point. This caused a regression in 7.2.0-rc1.

The fix is to wrap File.ResolveLinkTarget in a try/catch block, and use the original fileName when ResolveLinkTarget fails.

@iSazonov and @jborean93, thank you both for bring the regression to our attention, and also worked out the test.

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[adityapatwardhan]

@daxian-dbw New test is failing.. please have a look

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This PR has 37 quantified lines of changes. In general, a change size of upto 200 lines is ideal for the best PR experience!

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Total files changed: 2

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.cs : +5 -3
.ps1 : +29 -0

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[ghost]

🎉v7.2.0 has been released which incorporates this pull request.:tada:

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[t10-13rocket]

LGTM

[ghost]

🎉v7.3.0-preview.1 has been released which incorporates this pull request.:tada:

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