fix: Ensure stdout is py2/3 compatible

Author: sijis

packer.py

@@ -74,8 +74,8 @@ def fix(self, to_file=None):
         result = self.packer_cmd()
         if to_file:
             with open(to_file, 'w') as f:
-                f.write(result.stdout)
-        result.fixed = json.loads(result.stdout)
+                f.write(result.stdout.decode())
+        result.fixed = json.loads(result.stdout.decode())
         return result
 
     def inspect(self, mrf=True):
@@ -115,7 +115,7 @@ def inspect(self, mrf=True):
 
         result = self.packer_cmd()
         if mrf:
-            result.parsed_output = self._parse_inspection_output(result.stdout)
+            result.parsed_output = self._parse_inspection_output(result.stdout.decode())
         else:
             result.parsed_output = None
         return result