[chore] Move AWS ECS, EKS and Log attributes to the registry

[joaopgrassi]

Related to #407

Changes

Move AWS ECS, EKS and Log to the attributes registry

Merge requirement checklist

• CONTRIBUTING.md guidelines followed.
• Change log entry added, according to the guidelines in When to add a changelog entry.
  • If your PR does not need a change log, start the PR title with [chore]
• schema-next.yaml updated with changes to existing conventions.

[AlexanderWert]

Let's have a single aws file in the registry. See related comment in https://github.com/open-telemetry/semantic-conventions/pull/850/files#r1542415558.

[joaopgrassi]

Let's have a single aws file in the registry. See related comment in #850 (files).

@AlexanderWert fixed!