Value pg_probackup major_version added to the class Init

Author: egarbuz

testgres/plugins/pg_probackup2/pg_probackup2/init_helpers.py

@@ -204,6 +204,8 @@ def __init__(self):
 os.environ["PGAPPNAME"] = "pg_probackup"
 self.delete_logs = delete_logs
 
+self.major_version = int(self.probackup_version.split('.')[0])
+
 def test_env(self):
 return self._test_env.copy()