Fix ms test exception parsing (#897)

Author: SimonCropp

src/Verify.ExceptionParsing.Tests/ExceptionParsingTests.Error_EmptyList.verified.txt

@@ -1,4 +1,4 @@
 {
   Type: ParseException,
-  Message: Expected content to contain `Directory:` or `VerifyException : Directory:` at the start. Ensure the current stable of Verify is being used.
+  Message: Expected content to contain `Directory:`, or `VerifyException : Directory:`, or `VerifyException: Directory:` at the start. Ensure the current stable of Verify is being used.
 }

src/Verify.ExceptionParsing.Tests/ExceptionParsingTests.cs

@@ -120,7 +120,7 @@ public Task MsTest()
     {
         var exceptionMessage = $"""
             Test method TheTests.XAMLCombinerTests.TestOutput threw exception: 
-            VerifyException : Directory: {Environment.CurrentDirectory}
+            VerifyException: Directory: {Environment.CurrentDirectory}
             NotEqual:
               - Received: XAMLCombinerTests.TestOutput.received.xaml
                 Verified: XAMLCombinerTests.TestOutput.verified.xaml

src/Verify.ExceptionParsing/Parser.cs

@@ -119,6 +119,16 @@ void ThrowIfEmpty(string directory)
             return directory;
         }
 
+        // MsTest
+        if (firstLine.StartsWith("VerifyException: Directory: "))
+        {
+            var directory = firstLine[28..];
+
+            ThrowIfEmpty(directory);
+
+            return directory;
+        }
+
         if (firstLine.StartsWith("Directory: "))
         {
             var directory = firstLine[11..];
@@ -128,7 +138,7 @@ void ThrowIfEmpty(string directory)
             return directory;
         }
 
-        throw new ParseException("Expected content to contain `Directory:` or `VerifyException : Directory:` at the start.");
+        throw new ParseException("Expected content to contain `Directory:`, or `VerifyException : Directory:`, or `VerifyException: Directory:` at the start.");
     }
 
     static string TrimStart(string next, string prefix)