docs: Add docs for connecting airflow to aws secrets backend

airflow/plural/docs/aws-secrets-backend.md

@@ -0,0 +1,61 @@
+## Connecting to AWS Secrets Backend
+
+Airflow allows you the opportunity to connect to various services as a Secrets Backend as an alternative to using the 
+Airflow UI to manage connections. One of these services is [AWS Secrets Manager](https://airflow.apache.org/docs/apache-airflow-providers-amazon/stable/secrets-backends/aws-secrets-manager.html).
+Once you add below configurations, Airflow will be able to retrieve Secrets from AWS Secrets Manager (provided that they 
+have the same prefixes specified in the `KWARGS` config).
+
+In this scenario, the prefixes are `airflow/connections` & `airflow/variables`, so any values stored under the 
+`airflow/connections` prefix would be treated the same as an object stored in the `Admin >> Connections` menu of the 
+Airflow UI. Any values stored under the `airflow/variables` prefix would be treated the same as an object stored in the 
+`Admin >> Variables` menu of the Airflow UI.
+
+### edit values.yaml
+
+You'll then want to edit `airflow/helm/airflow/values.yaml` in your installation repo with something like:
+
+```yaml
+airflow:
+  airflow:
+    airflow:
+      config:
+        AIRFLOW__SECRETS__BACKEND: airflow.providers.amazon.aws.secrets.secrets_manager.SecretsManagerBackend
+        AIRFLOW__SECRETS__BACKEND_KWARGS: '{"connections_prefix": "airflow/connections","variables_prefix":
+          "airflow/variables"}'
+```
+
+Alternatively, you should be able to do this in the configuration section for airflow in your plural console as well.
+
+### add policy to AWS role
+
+When installing the Airflow Application, Plural added a default role for Airflow. The role will be called 
+`<your-cluster-name>-airflow`. You will need to add a policy to that role to allow it to access AWS Secrets Manager. You
+can use this policy as a starting point:
+
+```json
+{
+	"Version": "2012-10-17",
+	"Statement": [
+		{
+			"Sid": "VisualEditor0",
+			"Effect": "Allow",
+			"Action": [
+				"secretsmanager:GetRandomPassword",
+				"secretsmanager:ListSecrets"
+			],
+			"Resource": "*"
+		},
+		{
+			"Sid": "VisualEditor1",
+			"Effect": "Allow",
+			"Action": "secretsmanager:*",
+			"Resource": "arn:aws:secretsmanager:<insert-aws-region>:<insert-aws-account-number>:secret:airflow/*"
+		}
+	]
+}
+```
+
+### redeploy
+
+From there, you should be able to run `plural build --only airflow && plural deploy --commit "use aws secrets manager 
+backend"` to use the secrets backend