chore: update changelog for version 3.1.1

[Yun-Kim]

• update changelog for version 3.1.1

[github-actions]

CODEOWNERS have been resolved as:

CHANGELOG.md                                                            @DataDog/apm-python

[github-actions]

Bootstrap import analysis

Comparison of import times between this PR and main.

Summary

The average import time in this PR is: 231 ± 4 ms.

The average import time in main is: 236 ± 5 ms.

The import time difference between this PR and main is: -5.1 ± 0.2 ms.

Import time breakdown

The following import paths have shrunk:

ddtrace.auto 2.255 ms (0.98%)

ddtrace.bootstrap.sitecustomize 1.501 ms (0.65%)

ddtrace.bootstrap.preload 1.501 ms (0.65%)

ddtrace.internal.products 1.501 ms (0.65%)

ddtrace.internal.remoteconfig.client 0.730 ms (0.32%)

ddtrace 0.753 ms (0.33%)

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-03-26 21:16:49

Comparing candidate commit 13b1d39 in PR branch release.script/changelog-update-3.1.1 with baseline commit 03d8cf9 in branch main.

Found 0 performance improvements and 2 performance regressions! Performance is the same for 496 metrics, 2 unstable metrics.

scenario:iast_aspects-ospathbasename_aspect

• 🟥 execution_time [+234.952ns; +297.194ns] or [+7.184%; +9.087%]

scenario:iast_aspects-ospathsplitext_aspect

• 🟥 execution_time [+334.644ns; +404.152ns] or [+9.049%; +10.929%]