[CI] Migrate CI pipelines from Jenkins to BuildKite (#8142)

* [CI] Migrate CI pipelines from Jenkins to BuildKite

* Require manual approval

* Less verbose output when pulling Docker

* Remove us-east-2 from metadata.py

* Add documentation

* Add missing underscore

* Add missing punctuation

* More specific instruction

* Better paragraph structure

tests/buildkite/infrastructure/service-user/create_service_user.py

@@ -0,0 +1,44 @@
+import argparse
+import os
+
+import boto3
+
+current_dir = os.path.dirname(__file__)
+
+
+def main(args):
+    with open(
+        os.path.join(current_dir, "service-user-template.yml"), encoding="utf-8"
+    ) as f:
+        service_user_template = f.read()
+
+    stack_id = "buildkite-elastic-ci-stack-service-user"
+
+    print("Create a new IAM user with suitable permissions...")
+    client = boto3.client("cloudformation", region_name=args.aws_region)
+    response = client.create_stack(
+        StackName=stack_id,
+        TemplateBody=service_user_template,
+        Capabilities=[
+            "CAPABILITY_IAM",
+            "CAPABILITY_NAMED_IAM",
+        ],
+        Parameters=[{"ParameterKey": "UserName", "ParameterValue": args.user_name}],
+    )
+    waiter = client.get_waiter("stack_create_complete")
+    waiter.wait(StackName=stack_id)
+    user = boto3.resource("iam", region_name=args.aws_region).User(args.user_name)
+    key_pair = user.create_access_key_pair()
+    print("Finished creating an IAM users with suitable permissions.")
+    print(f"Access Key ID: {key_pair.access_key_id}")
+    print(f"Access Secret Access Key: {key_pair.secret_access_key}")
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--aws-region", type=str, required=True)
+    parser.add_argument(
+        "--user-name", type=str, default="buildkite-elastic-ci-stack-user"
+    )
+    args = parser.parse_args()
+    main(args)