Ares Connector: Multiple table points to the same schema

[lucafuji]

Describe the bug
Ares Connector caching the schema mapping, however multiple table points to the same schema object.

for _, table := range tables {
		cf.setTable(&table)
		err := cf.fetchAndSetEnumCases(&table)
		if err != nil {
			return err
		}
	}

To Reproduce
Following the examples/ReadMe.md, you will see an error like "Missing primary key" which is caused by this

Expected behavior
the different table should point to different schema object