add support for notification channels

[alexconlin]

Signed-off-by: Alex Conlin-Oakley 458604+alexconlin@users.noreply.github.com

Description

Adds support for configuring channels in the OpenSearch notifications plugin.

Issues Resolved

Closes #30

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[prudhvigodithi]

Thanks for the contribution @alexconlin, I will take a look at this PR and provide feedback shortly.
Adding @bbarani @phillbaker @peterzhuamazon

[prudhvigodithi]

The test initially failed with error

  Running [/home/runner/golangci-lint-1.29.0-linux-amd64/golangci-lint run --out-format=github-actions --verbose --timeout=10m] in [] ...
  Error: File is not `gofmt`-ed with `-s` (gofmt)
  Error: File is not `gofmt`-ed with `-s` (gofmt)

@alexconlin can you run golangci-lint run --out-format=github-actions on your local to replicate the error?
Thank you

[alexconlin]

@prudhvigodithi those errors should be fixed now. Please could you re-approve the test run?

[prudhvigodithi]

Thanks @alexconlin can you also run the https://github.com/hashicorp/terraform-plugin-docs, this should generate the resources and examples for this new notification support.

[prudhvigodithi]

LGTM, @alexconlin can you please generate the tfdocs?
@phillbaker please take a look when you get a chance. Thank you

[alexconlin]

@prudhvigodithi I have updated the documentation with tfplugindocs.

I notice that the url parameter has moved from Required to Optional. It does that when I generate docs on the main branch as well. It seems to be related to this issue in terraform-plugin-docs.

[shurkus]

Any news?

[bbarani]

@phillbaker can you please take a look when you get a chance?