Support additional services for gcp provider

[RamanaReddy0M]

• closes: Extend GCP sources #330

[RamanaReddy0M]

✗ ./cloudlist -p gcp                             

  _______             _____     __ 
 / ___/ /__  __ _____/ / (_)__ / /_
/ /__/ / _ \/ // / _  / / (_-</ __/
\___/_/\___/\_,_/\_,_/_/_/___/\__/ 

                projectdiscovery.io

[INF] Current cloudlist version 1.0.8 (latest)
[INF] Listing assets from gcp (dev) provider
gcf-sources-4200296701-us-central1.storage.googleapis.com
pd-cloudlist-test-bucket.storage.googleapis.com
us-central1-universal-team-426216-k5.cloudfunctions.net
[INF] Found 3 Hosts for gcp (dev)

[ehsandeep]

@RamanaReddy0M we can expose service name as part of json output as well, for example:

{
  "public": true,
  "provider": "gcp",
+ "service": "s3"
  "id": "staging",
  "dns_name": "screenshot-test-bucket.storage.googleapis.com"
}