[SVLS-4422] Support metrics with timestamps when the Extension is running

[DylanLovesCoffee]

What does this PR do?

Allows sendDistributionMetricWithDate to submit a metric with a timestamp when the Extension is running. Neither hot-shots nor Dogstatsd supports historical distribution metrics (more on the latter here and here).

The ability to send metrics with timestamps already existed but did not work when using the Extension.

Motivation

• SVLS-4422
• Related to:
  • TODO: https://github.com/DataDog/datadog-lambda-python/issues/398
  • https://github.com/DataDog/datadog-lambda-js/issues/58

Testing Guidelines

Unit test + manual tests. Example of one invocation using the following:

const MS_PER_MINUTE = 60000;
const timestamp = new Date(Date.now() - MS_PER_MINUTE);
sendDistributionMetricWithDate("dylan.test.past", 1, timestamp);
sendDistributionMetric("dylan.test.present", 1); // tracer.dogstatsd.distribution("dylan.test.present", 1) also works

Additional Notes

Types of Changes

• [ ] Bug fix
• [ ] New feature
• [ ] Breaking change
• [ ] Misc (docs, refactoring, dependency upgrade, etc.)

Check all that apply

• [ ] This PR's description is comprehensive
• [ ] This PR contains breaking changes that are documented in the description
• [ ] This PR introduces new APIs or parameters that are documented and unlikely to change in the foreseeable future
• [ ] This PR impacts documentation, and it has been updated (or a ticket has been logged)
• [ ] This PR's changes are covered by the automated tests
• [ ] This PR collects user input/sensitive content into Datadog
• [ ] This PR passes the integration tests (ask a Datadog member to run the tests)

[duncanista]

Do not merge before #519

[DylanLovesCoffee]

Do not merge before #519

should I just change the base to jordan.gonzalez/lazy-load-fallback-processor?