Update index.rst (#655)
Update index.rst (#655)

Spelling fix for `GPC` to `GCP`
confluentinc/examples,confluentinc/examples,confluentinc/examples,confluentinc/examples,confluentinc/examples,confluentinc/examples,confluentinc/examples,confluentinc/examples,confluentinc/examples,confluentinc/examples