Extend the use of OpenTelemetry to Core API entry points

[ciprianjichici]

Extend the use of OpenTelemetry to Core API entry points

The issue or feature being addressed

OpenTelemetry libraries have dependencies with vulnerabilities.
Core API entry points are not wrapped in telemetry activities.

Details on the issue fix or feature implementation

Update all NuGet package dependencies across the .NET projects.
Wrap completion endpoints in Core API with telemetry activities.

Confirm the following

• I started this PR by branching from the head of the default branch
• I have targeted the PR to merge into the default branch
• This PR needs to be cherry-picked into at least one release branch
• I have included unit tests for the issue/feature
• I have included inline docs for my changes, where applicable
• I have successfully run a local build
• I have provided the required update scripts, where applicable
• I have updated relevant docs, where applicable

Note

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