profiler: Reduce execution trace period to 15min

[felixge]

The initial value was very conservative, especially considering that this feature is opt-in for now. We expect this new value to be a better tradeoff between overhead, data volumes and span coverage.

What does this PR do?

Motivation

Describe how to test/QA your changes

Reviewer's Checklist

• Changed code has unit tests for its functionality.
• If this interacts with the agent in a new way, a system test has been added.

[pr-commenter]

Benchmarks

Benchmark execution time: 2023-07-04 07:41:11

Comparing candidate commit 7a41f17 in PR branch felix.geisendoerfer/PROF-7904-increase-interval with baseline commit 2c7a8f4 in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 27 metrics, 0 unstable metrics.