chore: update dependency opentelemetry.api to 1.15.1

[renovate-bot]

This PR contains the following updates:

Package	Change	Age	Confidence
OpenTelemetry.Api (source)	1.15.0 → 1.15.1

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Release Notes

open-telemetry/opentelemetry-dotnet (OpenTelemetry.Api)

v1.15.1

Release details: 1.15.1

• Breaking change: The Baggage API now disallows empty baggage names and
  treats baggage names and values as case sensitive, aligning with the latest
  Baggage API specification.
• Various bug fixes across OpenTelemetry.Api and OpenTelemetry SDK,
  including fixes for thread-safety, sampler edge cases, metrics precision,
  and observable instrument lifecycle handling.

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Configuration

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[gemini-code-assist]

Code Review

This pull request updates the OpenTelemetry.Api package version from 1.15.0 to 1.15.1 in the Google.Cloud.EntityFrameworkCore.Spanner project. Feedback highlights that this version bump introduces breaking changes to the Baggage API, specifically regarding empty baggage names and case sensitivity, which may necessitate updates to the codebase to prevent runtime failures.

[gemini-code-assist]

This update to OpenTelemetry.Api v1.15.1 introduces a breaking change in the Baggage API. According to the release notes, empty baggage names are now disallowed, and both names and values are treated as case-sensitive. This could lead to runtime failures if other parts of the codebase use the Baggage API and rely on the previous behavior. Any usage of the Baggage API may need to be updated to be compliant with the new specification.