fix: value of FindPostmasterResultCode::not_found is corrected

It was declared as a tuple (1,) , not a number (1).

Author: dmitry-lipetsk

src/impl/platforms/internal_platform_utils.py

@@ -9,7 +9,7 @@
 class InternalPlatformUtils:
     class FindPostmasterResultCode(enum.Enum):
         ok = 0
-        not_found = 1,
+        not_found = 1
         not_implemented = 2
         many_processes = 3
         has_problems = 4