Minor fix for T1115 - Pipe Get-Clipboard output (#952)

* Update T1115.yaml

Update command for PowerShell so the contents of Get-Clipboard are actually invoked as an expression.

* Update Markdown PowerShell code snippet to reflect changes

* Pipe output of Get-Clipboard to iex in order to invoke the value of clipboard as a command

Co-authored-by: Carrie Roberts <clr2of8@gmail.com>

atomics/T1115/T1115.md

@@ -63,7 +63,7 @@ Utilize PowerShell to echo a command to clipboard and execute it
 
 ```powershell
 echo Get-Process | clip
-iex Get-Clipboard
+Get-Clipboard | iex
 ```
 
 

atomics/T1115/T1115.yaml

@@ -29,4 +29,4 @@ atomic_tests:
     elevation_required: false
     command: |
       echo Get-Process | clip
-      iex Get-Clipboard
+      Get-Clipboard | iex