[Azure] Set elastic/obs-cloud-monitoring team as owner of azure-eventhub input

[zmoog]

What does this PR do?

Set elastic/obs-cloud-monitoring team as the owner of azure-eventhub input.

Why is it important?

The azure-eventhub input doesn't have an owner and all review requests land on the elastic/agent-data-plane desk.

The elastic/obs-cloud-monitoring maintained this input in the last 12+ months, so we are a good candidate to own this input.

[mergify]

This pull request does not have a backport label.
If this is a bug or security fix, could you label this PR @zmoog? 🙏.
For such, you'll need to label your PR with:

• The upcoming major version of the Elastic Stack
• The upcoming minor version of the Elastic Stack (if you're not pushing a breaking change)

To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-v8./d.0 is the label to automatically backport to the 8./d branch. /d is the digit

[elasticmachine]

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• Start Time: 2023-05-31T08:07:06.555+0000

• Duration: 13 min 42 sec

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Passed	3
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Total	3

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