Fix unit test broken by LfMergeBridge's new logic

LfMergeBridge has become smarter about finding the location of FixFwData
so the test that checks what happens if it's missing now has to work a
lot harder to hide it. It used to be enough to simply change the current
working directory, but now we have to actually hide the FixFwData file
AND the FixFwData.exe file by renaming them temporarily.

src/LfMerge.Core.Tests/Actions/SynchronizeActionBridgeIntegrationTests.cs

@@ -96,16 +96,37 @@ public void Teardown()
 		[Test]
 		public void MissingFwDataFixer_Throws()
 		{
-			// Setup
-			var tmpFolder = Path.Combine(_languageDepotFolder.Path, "WorkDir");
-			Directory.CreateDirectory(tmpFolder);
-			Directory.SetCurrentDirectory(tmpFolder);
-
-			// Execute/Verify
-			Assert.That(() => _synchronizeAction.Run(_lfProject),
-				// This can't happen in real life because we ensure that we have a clone
-				// before we call sync. Therefore it is acceptable to get an exception.
-				Throws.TypeOf<InvalidOperationException>());
+			// This used to just change the current directory, which was enough when LfMergeBridge only
+			// looked for FixFwData in the current directory. However, LfMergeBridge is now smart enough
+			// to look for FixFwData in the folder where LfMergeBridge.dll is being run from, which finds
+			// it no matter the current working directory. So we need to move it out of the way, and ensure
+			// that it gets moved back at the end of the test so other tests don't start failing.
+
+			string fixFwDataPath = null;
+			string fixFwDataExePath = null;
+			try {
+				// Setup
+				var assembly = typeof(LfMergeBridge.LfMergeBridge).Assembly;
+				var dir = Directory.GetParent(assembly.Location).FullName;
+				if (File.Exists(Path.Join(dir, "FixFwData"))) {
+					fixFwDataPath = Path.Join(dir, "FixFwData");
+					File.Move(fixFwDataPath, fixFwDataPath + ".renamed");
+				}
+				if (File.Exists(Path.Join(dir, "FixFwData.exe"))) {
+					fixFwDataExePath = Path.Join(dir, "FixFwData.exe");
+					File.Move(fixFwDataExePath, fixFwDataExePath + ".renamed");
+				}
+
+				// Execute/Verify
+				Assert.That(() => _synchronizeAction.Run(_lfProject),
+					// This can't happen in real life because we ensure that we have a clone
+					// before we call sync. Therefore it is acceptable to get an exception.
+					Throws.TypeOf<InvalidOperationException>());
+
+			} finally {
+				if (fixFwDataPath != null) File.Move(fixFwDataPath + ".renamed", fixFwDataPath);
+				if (fixFwDataExePath != null) File.Move(fixFwDataExePath + ".renamed", fixFwDataExePath);
+			}
 		}
 
 		[Test]