Update get_sql_column_sample_data.py

When CheckAll is not true the script didn't assign the str variable scriptEnd prior to trying to add to it with +=.

lib/modules/powershell/collection/get_sql_column_sample_data.py

@@ -74,7 +74,8 @@ def generate(self, obfuscate=False, obfuscationCommand=""):
         instance = self.options['Instance']['Value']
         no_defaults = self.options['NoDefaults']['Value']
         check_all = self.options['CheckAll']['Value']
-
+        scriptEnd = ""
+
         # read in the common module source code
         moduleSource = self.mainMenu.installPath + "data/module_source/collection/Get-SQLColumnSampleData.ps1"
         script = ""