fix: [CI-11840]: Added env variable to control the event of inbound w…

[ShobhitSingh11]

Have added the env var "DRONE_INCOMING_WEBHOOK_EVENTS" (of type list of string) to control the event in case of incoming webhook. If no such env variable is provided then it will fallback to default behaviour. Below are the test cases

• Case 1: When no env variable "DRONE_INCOMING_WEBHOOK_EVENTS" is present.

https://github.com/harness/gitness/assets/139750384/ad228d61-2608-4756-abaa-b3397eba1fb7

• Case 2: When Deployment event is missing from env var.

https://github.com/harness/gitness/assets/139750384/0faf2afc-9e0b-42f1-9327-8dc674ed112d

• Case 3: When Deployment, pull_request events are missing from env var.

https://github.com/harness/gitness/assets/139750384/29f40107-4b7a-4eae-afa8-464d78662e8b

• Case 4: When Deployment and push events are only present in env var.

https://github.com/harness/gitness/assets/139750384/b6cdec79-20bb-4d56-8fd0-f72cb9e57a8e

Tested with few more combinations as well.