Bump main pre-release version iteration to preview4

[carlossanlop]

Must only merge after the snap is done. Edit: The snap has been done: release/8.0-preview3

cc @radical@lewing@steveisok in case we see any unexpected wasm/mono issues due to version bumping.

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Issue Details

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Must only merge after the snap is done.

Author:	carlossanlop
Assignees:	carlossanlop
Labels:	area-Infrastructure-libraries
Milestone:	-

[steveisok]

the WBT failure is:

Wasm.Build.NativeRebuild.Tests.FlagsChangeRebuildTests.ExtraEmccFlagsSetButNoRealChange(buildArgs: BuildArgs { ProjectName = placeholder, Config = Release, AOT = False, ProjectFileContents = placeholder, ExtraBuildArgs = }, extraCFlags: "/p:EmccExtraCFlags=-g", extraLDFlags: "", host: Chrome, id: "xzggs025.tve") [FAIL]
System.AggregateException : One or more errors occurred. (One or more errors occurred. (A task was canceled.)) (The process cannot access the file '\\?\C:\helix\work\workitem\e\wbt\xzggs025.tve' because it is being used by another process.)
---- System.AggregateException : One or more errors occurred. (A task was canceled.)
-------- System.Threading.Tasks.TaskCanceledException : A task was canceled.
---- System.IO.IOException : The process cannot access the file '\\?\C:\helix\work\workitem\e\wbt\xzggs025.tve' because it is being used by another process.

@lewing@radical any ideas?

[carlossanlop]

@steveisok is that a new failure? If you think it is not related to this change, I can open an issue to track it separately, so I can unblock this PR. (From that error message you shared, it does not look very related to this change).

[steveisok]

@steveisok is that a new failure? If you think it is not related to this change, I can open an issue to track it separately, so I can unblock this PR. (From that error message you shared, it does not look very related to this change).

I'm not sure if it's a new failure. I don't think the version bump is causing this, so can you make a known issue out of it?

[carlossanlop]

CI failures:

• Existing: [trimming] Test failures only when trimming #73961
• Execution timeout. Affected queues:
  • browser-wasm windows Release LibraryTests_AOT
  • browser-wasm windows Release Mono_DebuggerTests_chrome
  • I'll open an issue if I see this happen more often.
• I also opened: [wasm] SimpleSourceChangeRebuildTest.SimpleStringChangeInSource - Long running test error, cannot access file used by another process #83752