AWS IRSA support and Eventbridge reaction

[ruokun-niu]

Description

This PR adds two types of new identity: AwsIamRole and AwsAccessKey.

This PR also adds the AWS EventBridge reaction, which only supports authentication using one of the two identity types listed above. If using IRSA, the IAM role must have the PutEvents permission for Eventbridge.

Sample yaml using IRSA:

kind: Reaction
apiVersion: v1
name: drasi-eventbridge
spec:
  kind: EventBridge
  identity:
    kind: AwsIamRole
    roleArn:  <role-arn>
  queries:
   <query-id>:
  properties: 
    eventBusName: xxxxx

Sample yaml using AwsAccessKey:

kind: Reaction
apiVersion: v1
name: drasi-eventbridge-2
spec:
  kind: EventBridge
  identity:
    kind: AwsIamAccessKey
    accessKeyId: 
      kind: Secret
      name: eventbridge-creds
      key: accessKeyId
    secretAccessKey: 
      kind: Secret
      name: eventbridge-creds
      key: secretAccessKey
     region: <region>
  queries:
    <query-id>:
  properties: 
    eventBusName: xxx

Type of change

• This pull request fixes a bug in Drasi and has an approved issue (issue link required).
• This pull request adds or changes features of Drasi and has an approved issue (issue link required).
• This pull request is a minor refactor, code cleanup, test improvement, or other maintenance task and doesn't change the functionality of Drasi (issue link optional).

Fixes: #issue_number