Codeblock array should use single quotes (#147)

Super minor, but the TargetVersions array inside of the hashtable should use single quotes for constant strings. Given the docs actually have a section on using single quotes for constant strings, I figured it was probably appropriate to submit a small PR for this :).

Author: dotnvo

reference/docs-conceptual/PSScriptAnalyzer/Rules/UseCompatibleSyntax.md

@@ -22,9 +22,9 @@ PowerShell versions because they aren't able to parse the incompatible syntaxes.
         PSUseCompatibleSyntax = @{
             Enable = $true
             TargetVersions = @(
-                "6.0",
-                "5.1",
-                "4.0"
+                '6.0',
+                '5.1',
+                '4.0'
             )
         }
     }