feat(ddtrace/opentelemetry): update expected span names based on otelhttp version

[darccio]

What does this PR do?

Adapts assertions to allow otelhttp related test according to its version, as v0.61.0 introduces a new default semantic conventions version.

Motivation

Allow our smoke tests to handle the breaking change.

Reviewer's Checklist

• Changed code has unit tests for its functionality at or near 100% coverage.
• System-Tests covering this feature have been added and enabled with the va.b.c-dev version tag.
• There is a benchmark for any new code, or changes to existing code.
• If this interacts with the agent in a new way, a system test has been added.
• New code is free of linting errors. You can check this by running golangci-lint run locally.
• Add an appropriate team label so this PR gets put in the right place for the release notes.
• Non-trivial go.mod changes, e.g. adding new modules, are reviewed by @DataDog/dd-trace-go-guild.

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[pr-commenter]

Benchmarks

Benchmark execution time: 2025-05-26 21:32:27

Comparing candidate commit 0355147 in PR branch dario.castane/otel-breaking-change-20250526 with baseline commit 31f6d0d in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 21 metrics, 0 unstable metrics.