feat(266): Add extraObjects to Helm Chart.

[patpicos]

What does this PR do?

Allows the creation of additional resources from the helm chart such as SecretStore/ExternalSecret resources. This is a common approach followed by many open-source charts Solves: https://github.com/cloudability/metrics-agent/issues/266

Where should the reviewer start?

Helm Chart

How should this be manually tested?

Comment out the sample resource in values.yaml and run helm template .

Any background context you want to provide?

What picture best describes this PR (optional but encouraged)?

N/A

What are the relevant Github Issues?

https://github.com/cloudability/metrics-agent/issues/266

Developer Done List

• [X] Tests Added/Updated
• [X] Updated README.md - No changes to readme
• [X] Verified backward compatible - Default value in place in values.yaml with a empty array
• [X] Verified database migrations will not be catastrophic - Not Applicable
• [X] Considered Security, Availability and Confidentiality

For the Reviewer:

By approving this PR, the reviewer acknowledges that they have checked all items in this done list.

Reviewer/Approval Done List

• [ ] Tests Pass Locally
• [ ] CI Build Passes
• [ ] Verified README.md is updated
• [ ] Verified changes are backward compatible
• [ ] Reviewed impact to Security, Availability and Confidentiality (if issue found, add comments and request changes)

[CLAassistant]

All committers have signed the CLA.

[patpicos]

@jyin-apptio @daniel-spray @jdhudson3 is this something you could review? I dont have access to add reviewers directly

[daniel-spray]

Hi @patpicos Thank you for your contribution! We have included these changes in the 2.11.30 release of the metrics-agent!

[patpicos]

Cheers! thanks for getting this included. Timing is perfect as we were finalizing our integration internally w/ a fork. This allows us to eliminate the fork and use upstream.