Notebook(Alerts): PagerDuty routing key stored in plain text in script

## About the bug

**Steps to reproduce:**
List the minimal actions needed to reproduce the behavior.

1. Setup a Pager Duty account and generate a routing key.
2. Go to Influxdbv2 UI (note that during this test the feature flag 'notebooksNewEndpoints' was set)
3. Add test data to a bucket
4. Create an Alert Notebook
5. Use the test data to define the query
6. In the alert section choose PagerDuty
7. Add a URL back to the notebook as Client URL
8. Add the routing key. Is masked like a password.
9. Click 'Export Alert Task'
10. Tasks > Open newly created task > Edit

**Expected behavior:**

Expected that sensitive value would be hashed or stored as a secret.

**Actual behavior:**

The routing key is stored in plain text.

**Visual Proof:**



## About your environment

**Environment info:**

Testing in K8SIDPE remocal

latest commit project ui

```
commit 7f6a7997396b4cbae41cb300cafaac4306e73b56 (HEAD -> master, upstream/master, origin/master, origin/HEAD)
Author: wiedld
Date: Fri Feb 18 16:40:49 2022 -0800
```

latest commit project K8SIDPE

```
commit 39c95a0c4ff722649d49c14bef5eb5f5726afebf (HEAD -> master, origin/master, origin/alchemy/automatic, origin/HEAD)
Author: Hercules Mango Churchill
Date: Sat Feb 19 01:41:48 2022 +0000
```

No source files or tests are named. Start by reproducing the PagerDuty Alert Notebook flow through exporting and editing the alert task, then trace where the routing key is serialized; done means the exported or stored task no longer exposes the routing key in plain text and the behavior is covered by a regression test.

Written by the indexing model from the issue text.