fix(pagerduty): migrate from deprecated pdpyras to pagerduty package (#1837)

[leaf5135]

Summary

This PR migrates the PagerDuty integration from the deprecated pdpyras package to the new supported pagerduty package. It updates dependencies and refactors code to use the new API. This change resolves deprecation warnings and ensures long-term support and compatibility.

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Related issues or links

• https://github.com/cartography-cncf/cartography/issues/1837

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Checklist

Provide proof that this works (this makes reviews move faster). Please perform one or more of the following:

• [ ] Update/add unit or integration tests.
• [ ] Include a screenshot showing what the graph looked like before and after your changes.
• [x] Include console log trace showing what happened before and after your changes.

If you are changing a node or relationship:

• [ ] Update the [schema](https://github.com/cartography-cncf/cartography/tree/master/docs/root/modules) and [readme](https://github.com/cartography-cncf/cartography/blob/master/docs/schema/README.md).

If you are implementing a new intel module:

• [ ] Use the NodeSchema [data model](https://cartography-cncf.github.io/cartography/dev/writing-intel-modules.html#defining-a-node).

[achantavy]

Hey @leaf5135 thanks for taking this on! Just wondering, have you tried this on PD yet? If not that's ok, I can try manually test later

[leaf5135]

@achantavy Not yet — feel free to run it on your end in PD