chore: add .env to .gitignore

[P403n1x87]

A .env file can be used to configure the local development environment (e.g. enabling build features like DD_SETUP_CACHE_DOWNLOADS. We add this file to the .gitignore so that it can be ignored from the index.

Checklist

• PR author has checked that all the criteria below are met
• The PR description includes an overview of the change
• The PR description articulates the motivation for the change
• The change includes tests OR the PR description describes a testing strategy
• The PR description notes risks associated with the change, if any
• Newly-added code is easy to change
• The change follows the library release note guidelines
• The change includes or references documentation updates if necessary
• Backport labels are set (if applicable)

Reviewer Checklist

• Reviewer has checked that all the criteria below are met
• Title is accurate
• All changes are related to the pull request's stated goal
• Avoids breaking API changes
• Testing strategy adequately addresses listed risks
• Newly-added code is easy to change
• Release note makes sense to a user of the library
• If necessary, author has acknowledged and discussed the performance implications of this PR as reported in the benchmarks PR comment
• Backport labels are set in a manner that is consistent with the release branch maintenance policy

[github-actions]

CODEOWNERS have been resolved as:

.gitignore                                                              @DataDog/apm-core-python

[github-actions]

Bootstrap import analysis

Comparison of import times between this PR and base.

Summary

The average import time from this PR is: 273 ± 2 ms.

The average import time from base is: 275 ± 2 ms.

The import time difference between this PR and base is: -2.23 ± 0.09 ms.

Import time breakdown

The following import paths have shrunk:

ddtrace.auto 2.036 ms (0.75%)

ddtrace.bootstrap.sitecustomize 1.358 ms (0.50%)

ddtrace.bootstrap.preload 1.358 ms (0.50%)

ddtrace.internal.remoteconfig.client 0.634 ms (0.23%)

ddtrace 0.678 ms (0.25%)

ddtrace.internal._unpatched 0.031 ms (0.01%)

json 0.031 ms (0.01%)

json.decoder 0.031 ms (0.01%)

re 0.031 ms (0.01%)

enum 0.031 ms (0.01%)

types 0.031 ms (0.01%)

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-06-14 14:52:04

Comparing candidate commit 851025e in PR branch chore/ignore-dotenv with baseline commit 990b1bf in branch main.

Found 0 performance improvements and 4 performance regressions! Performance is the same for 557 metrics, 3 unstable metrics.

scenario:iastaspects-format_map_aspect

• 🟥 execution_time [+407.816ns; +466.394ns] or [+12.686%; +14.508%]

scenario:iastaspectsospath-ospathbasename_aspect

• 🟥 execution_time [+458.554ns; +658.336ns] or [+10.831%; +15.550%]

scenario:iastaspectsospath-ospathjoin_aspect

• 🟥 execution_time [+782.284ns; +928.449ns] or [+12.692%; +15.064%]

scenario:iastaspectsospath-ospathnormcase_aspect

• 🟥 execution_time [+294.522ns; +377.400ns] or [+8.516%; +10.913%]