### Apache Airflow Provider(s)

pagerduty

### Versions of Apache Airflow Providers

apache-airflow-providers-pagerduty==2.0.1

### Apache Airflow version

2.1.4 (latest released)

### Operating System

macOS catalina

### Deployment

Virtualenv installation

### Deployment details

_No response_

### What happened

Currently, the PagerdutyHook can be used to access two API's: 
- Events API: interface to send alerts. Needs only  a integration key/routing key/Events API key. (https://developer.pagerduty.com/docs/get-started/getting-started/#events-api)
- Pagerduty API: interface to interact with account data, project setup, etc. Needs only a Pagerduty rest API Key or account token. (https://developer.pagerduty.com/docs/get-started/getting-started/#rest-api)

In order to interact with the API's, the PagerdutyHook uses two attributes that refer to these api keys: 
- `token`:  Refers to the account token/rest API key. This attribute is retrieved from the `Password` field in the connection or can be set at initialization of a class instance by passing it into the init method of the class.  In the __Init__ method, its value is asserted to be not `None`. The token is **not used** for sending alerts to Pagerduty.
- `routing_key`: Refers to the integration key/Events API key. This attribute is retrieved from the `Extra` field and is used in the `create_event` method to send request to the Events API. In the `create_event` method the value is asserted to be not `None`.

As a result if users want to use the hook to only send events, they will need to provide a connection with a random string as a password (which can't be None) and the actual integration key in the `extra` field. This to me makes no sense. 

**Proposed solution:** Rather than having the two api's in a single hook, separate them into two different hooks. This increases code simplicity and maintainability.

### What you expected to happen

_No response_

### How to reproduce

_No response_

### Anything else

_No response_

### Are you willing to submit PR?

- [X] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

airflow/providers/pagerduty/hooks/pagerduty.py
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"""Hook for sending or receiving data from PagerDuty as well as creating PagerDuty incidents."""
from typing import Any, Dict, List, Optional
import pdpyras
from airflow.exceptions import AirflowException
from airflow.hooks.base import BaseHook
class PagerdutyHook(BaseHook):