Update documentation for INTL0003 to explain test method exception

Co-authored-by: BenjaminMichaelis <22186029+BenjaminMichaelis@users.noreply.github.com>

Author: Copilot

docs/analyzers/00XX.Naming.md

@@ -49,6 +49,8 @@ class SomeClass
 
 Methods, including local functions, should be PascalCase
 
+**Note:** Test methods decorated with test framework attributes (e.g., `[TestMethod]`, `[Fact]`, `[Theory]`, `[Test]`) are exempt from this rule, as they commonly use underscores for readability (e.g., `Method_Scenario_ExpectedResult`).
+
 **Allowed**
 ```c#
 class SomeClass
@@ -66,6 +68,19 @@ class SomeClass
 }
 ```
 
+**Allowed (Test Methods)**
+```c#
+[TestClass]
+public class SomeClassTests
+{
+    [TestMethod]
+    public void GetEmpty_WhenCalled_ReturnsEmptyString() 
+    {
+        // Test implementation
+    }
+}
+```
+
 **Disallowed**
 ```c#
 class SomeClass