Clarify what alias to use

src/libraries/Fuzzing/DotnetFuzzing/IFuzzer.cs

@@ -8,7 +8,8 @@ internal interface IFuzzer
     /// <summary>Friendly name to identify this fuzz target in OneFuzz configuration.</summary>
     string Name => GetType().Name;
 
-    /// <summary>Alias to assign crash report work items to.</summary>
+    /// <summary>Alias to assign crash report work items to.
+    /// The is a Microsoft alias, not your GitHub username.</summary>
     string BlameAlias { get; }
 
     /// <summary>List of assemblies that should be instrumented.

src/libraries/Fuzzing/README.md

@@ -88,6 +88,8 @@ internal sealed class IPAddressFuzzer : IFuzzer
 ```
 
 - `BlameAlias` specifies who should be assigned work items if automated fuzzing discovers a bug.
+  - Note that these work items are filed in a Microsoft-internal system, so this must be a Microsoft alias.
+  - If you don't have one, feel free to pick a "victim" from the relevant area owners.
 - `TargetAssemblies` is a list of assemblies where the tested code lives and that must be instrumented.
 - `TargetCoreLibPrefixes` is the same, but for types/namespaces in `System.Private.CoreLib`.
 - `FuzzTarget` is the logic that the fuzzer will run for every test input. It should exercise code from the target assemblies.