Add docs for new .NET MethodInvocation tracing

Adds docs around the new .NET MethodInvocation tracing call introduced
in PowerShell 7.6. This new tracing method allows you to see what method
overload was invoked inside the tracing context.

Author: jborean93

reference/7.6/Microsoft.PowerShell.Core/About/about_Methods.md

@@ -257,6 +257,40 @@ specific overload of the **Bar** method.
 int: 1
 ```
 
+## Finding what overload was used
+
+Since PowerShell 7.6, it is now possible to see what method overload was chosen
+by PowerShell. This is achieved through the new `MethodInvocation` tracing
+command.
+
+This example shows how to use `Trace-Command` to display the overload chosen
+when calling the [String.Split method](/dotnet/api/system.string.split).
+
+```powershell
+Trace-Command -PSHost -Name MethodInvocation -Expression {
+    "a 1 b 1 c 1 d".Split(1)
+}
+
+Trace-Command -PSHost -Name MethodInvocation -Expression {
+    "a 1 b 1 c 1 d".Split("1")
+}
+```
+
+```Output
+DEBUG: ... MethodInvocation Information: 0 : Invoking method: string[] Split(char separator, System.StringSplitOptions options = System.StringSplitOptions.None)
+
+a 1 b 1 c 1 d
+
+DEBUG: ... MethodInvocation Information: 0 : Invoking method: string[] Split(string separator, System.StringSplitOptions options = System.StringSplitOptions.None)
+a
+ b
+ c
+ d
+```
+
+In the first example the `1` was casted as a `[char]` and not a string causing
+the split output to split by `[char]1` and not the character `"1"`.
+
 ## Using .NET methods that take filesystem paths
 
 PowerShell supports multiple runspaces per process. Each runspace has its own
@@ -275,3 +309,4 @@ method.
 - [about_Member-Access_Enumeration](about_Member-Access_Enumeration.md)
 - [about_Properties](about_Properties.md)
 - [Get-Member](xref:Microsoft.PowerShell.Utility.Get-Member)
+- [Trace-Command](xref:Microsoft.PowerShell.Utility.Trace-Command)