Revert "Disable Net5CompatFileStream by default (#50166)"

[carlossanlop]

Partially addresses #51141

Unblocks dotnet/sdk#16810

This reverts commit 8b2ad5b to unblock dotnet/sdk.

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Issue Details

---

Partially addresses #51141

Unblocks dotnet/sdk#16810

This reverts commit 8b2ad5b to unblock dotnet/sdk.

Author:	carlossanlop
Assignees:	carlossanlop
Labels:	area-System.IO
Milestone:	6.0.0

[adamsitnik]

@carlossanlop thank you for doing this! I hope to have a bug fix tomorrow

[jeffhandley]

Thanks, @carlossanlop. Out of curiosity, could we alternatively enable the compat switch in the SDK project(s) to unblock that build? Or do you think there are too many projects affected by the bug right now?

[carlossanlop]

Out of curiosity, could we alternatively enable the compat switch in the SDK project(s) to unblock that build? Or do you think there are too many projects affected by the bug right now?

I am unsure of the impact on other repos. We think it's safer at this point having this change reverted, do our tests again, make sure the issue is reproduced locally, and get it fixed before we turn on the compat switch by default again.

[jeffhandley]

Makes sense; thanks!

[adamsitnik]

I have a fix, please don't merge this PR ;)

[adamsitnik]

Fix of the actual bug: #51151

[carlossanlop]

Thanks Adam! If the CI in your PR finishes successfully, we will merge that. Otherwise, we'll merge this PR.