Remove some hard coded path separatoes from build.fsx

Just a tiny bit more if the .NET 8 update PR broken out

Author: Numpsy

build.fsx

@@ -660,7 +660,7 @@ Target.create "DotNetCoreIntegrationTests" (fun _ ->
 
     runExpecto
         root
-        "src/test/Fake.Core.IntegrationTests/bin/Release/net6.0/Fake.Core.IntegrationTests.dll"
+        ("src" </> "test" </> "Fake.Core.IntegrationTests" </> "bin" </> "Release" </> "net6.0" </> "Fake.Core.IntegrationTests.dll")
         "Fake_Core_IntegrationTests.TestResults.xml")
 
 Target.create "TemplateIntegrationTests" (fun _ ->
@@ -676,13 +676,13 @@ Target.create "DotNetCoreUnitTests" (fun _ ->
     // dotnet run -p src/test/Fake.Core.UnitTests/Fake.Core.UnitTests.fsproj
     runExpecto
         root
-        "src/test/Fake.Core.UnitTests/bin/Release/net6.0/Fake.Core.UnitTests.dll"
+        ("src" </> "test" </> "Fake.Core.UnitTests" </> "bin" </> "Release" </> "net6.0" </> "Fake.Core.UnitTests.dll")
         "Fake_Core_UnitTests.TestResults.xml"
 
     // dotnet run --project src/test/Fake.Core.CommandLine.UnitTests/Fake.Core.CommandLine.UnitTests.fsproj
     runExpecto
         root
-        "src/test/Fake.Core.CommandLine.UnitTests/bin/Release/net6.0/Fake.Core.CommandLine.UnitTests.dll"
+        ("src" </> "test" </> "Fake.Core.CommandLine.UnitTests" </> "bin" </> "Release" </> "net6.0" </> "Fake.Core.CommandLine.UnitTests.dll")
         "Fake_Core_CommandLine_UnitTests.TestResults.xml")
 
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