feat: Add support for aggregator type in DataDog metric provider

[NaurisSadovskis]

This pull request adds ability to override default DataDog (v2) API aggregator (last) for metrics-based queries [docs].

We stumbled upon this issue when using count-based distributed metrics and moving_rollup() function which aggregates data points in a given time period [docs]:

Querying this data via DataDog API (and a formula b) reported the last value as 17.0:

Response: {"data":{"type":"scalar_response","attributes":{"columns":[{"values":[17.0],"name":"moving_rollup(b, 180, 'sum')","type":"number","meta":{"unit":null}}]}}}

Switching aggregator from last to sum behaves as expected.
Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this is a chore.
• The title of the PR is (a) conventional with a list of types and scopes found here, (b) states what changed, and (c) suffixes the related issues number. E.g. "fix(controller): Updates such and such. Fixes #1234".
• I've signed my commits with DCO
• I have written unit and/or e2e tests for my change. PRs without these are unlikely to be merged.
• My builds are green. Try syncing with master if they are not.
• My organization is added to USERS.md.

[NaurisSadovskis]

cc: @meeech and @zachaller since both of you seem to be involved in getting DataDog API v2 functionality out :)

[github-actions]

Go Published Test Results

2 097 tests   2 097 ✅  2m 49s ⏱️
  118 suites      0 💤
    1 files        0 ❌

Results for commit 68cf420.

♻️ This comment has been updated with latest results.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (c688dd8) 81.82% compared to head (68cf420) 81.83%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3293      +/-   ##
==========================================
+ Coverage   81.82%   81.83%   +0.01%     
==========================================
  Files         135      135              
  Lines       20633    20636       +3     
==========================================
+ Hits        16882    16888       +6     
+ Misses       2880     2877       -3     
  Partials      871      871              

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[github-actions]

E2E Tests Published Test Results

  4 files    4 suites   3h 28m 30s ⏱️
106 tests  98 ✅  6 💤  2 ❌
436 runs  400 ✅ 24 💤 12 ❌

For more details on these failures, see this check.

Results for commit 68cf420.

♻️ This comment has been updated with latest results.

[meeech]

Hey @NaurisSadovskis

thanks for this. Looks good overall. See my 2 comments. feel free to reach out on slack if you have any q's

[meeech]

@NaurisSadovskis One other thing I forgot - please have a look at the docs and update those to explain using this new option.

[zachaller]

Is this ready for a final review?

[NaurisSadovskis]

@zachaller @meeech - yes, this is ready for final review!

[meeech]

@NaurisSadovskis Thanks again for doing this pr. Sorry about the delay on getting back to it.

Looks 👍🏼

One minor nit fix in the docs, but otherwise good to go

[sonarqubecloud]

Quality Gate passed

The SonarCloud Quality Gate passed, but some issues were introduced.

1 New issue
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[zachaller]

Thank you for the contribution!