feat: update otlp sdk version and add metric tags

[P1sar]

• version of OTLP bumped to the latest stable
• some changes due to severe API upgrade of the OTLP SDK
• refactored main metric structures

Description

Related Issue Or Context

Closes: #189

How Has This Been Tested? Testing details.

Tested locally with DataDog

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation

Checklist:

• I have commented my code, particularly in hard-to-understand areas.
• I have ensured that all acceptance criteria (or expected behavior) from issue are met
• I have updated the documentation locally and in docs.
• I have added tests to cover my changes.
• I have ensured that all the checks are passing and green, I've signed the CLA bot

[github-actions]

Go Test coverage is 65.9 %\ ✨ ✨ ✨

[github-actions]

Go Test coverage is 65.9 %\ ✨ ✨ ✨

[github-actions]

Go Test coverage is 65.7 %\ ✨ ✨ ✨