only load fetch plugin when fetch is used

[rochdev]

What does this PR do?

Only load fetch plugin when fetch is used.

Motivation

Right now it's always loaded regardless of whether it's used, which impacts startup time.

[github-actions]

Overall package size

Self size: 8.68 MB
Deduped: 94.88 MB
No deduping: 95.4 MB

Dependency sizes

| name | version | self size | total size | |------|---------|-----------|------------| | @datadog/libdatadog | 0.4.0 | 29.44 MB | 29.44 MB | | @datadog/native-appsec | 8.4.0 | 19.25 MB | 19.26 MB | | @datadog/native-iast-taint-tracking | 3.3.0 | 13.77 MB | 13.78 MB | | @datadog/pprof | 5.5.1 | 9.79 MB | 10.17 MB | | protobufjs | 7.2.5 | 2.77 MB | 5.16 MB | | @datadog/native-iast-rewriter | 2.8.0 | 2.6 MB | 2.74 MB | | @opentelemetry/core | 1.14.0 | 872.87 kB | 1.47 MB | | @datadog/native-metrics | 3.1.0 | 1.06 MB | 1.46 MB | | @opentelemetry/api | 1.8.0 | 1.21 MB | 1.21 MB | | import-in-the-middle | 1.11.2 | 112.74 kB | 835.4 kB | | source-map | 0.7.4 | 226 kB | 226 kB | | opentracing | 0.14.7 | 194.81 kB | 194.81 kB | | lru-cache | 7.18.3 | 133.92 kB | 133.92 kB | | pprof-format | 2.1.0 | 111.69 kB | 111.69 kB | | @datadog/sketches-js | 2.1.0 | 109.9 kB | 109.9 kB | | lodash.sortby | 4.7.0 | 75.76 kB | 75.76 kB | | ignore | 5.3.2 | 53.63 kB | 53.63 kB | | shell-quote | 1.8.1 | 44.96 kB | 44.96 kB | | istanbul-lib-coverage | 3.2.0 | 29.34 kB | 29.34 kB | | rfdc | 1.3.1 | 25.21 kB | 25.21 kB | | @isaacs/ttlcache | 1.4.1 | 25.2 kB | 25.2 kB | | tlhunter-sorted-set | 0.1.0 | 24.94 kB | 24.94 kB | | limiter | 1.1.5 | 23.17 kB | 23.17 kB | | dc-polyfill | 0.1.4 | 23.1 kB | 23.1 kB | | retry | 0.13.1 | 18.85 kB | 18.85 kB | | semifies | 1.0.0 | 15.84 kB | 15.84 kB | | jest-docblock | 29.7.0 | 8.99 kB | 12.76 kB | | crypto-randomuuid | 1.0.0 | 11.18 kB | 11.18 kB | | ttl-set | 1.0.0 | 4.61 kB | 9.69 kB | | path-to-regexp | 0.1.12 | 6.6 kB | 6.6 kB | | koalas | 1.0.2 | 6.47 kB | 6.47 kB | | module-details-from-path | 1.0.3 | 4.47 kB | 4.47 kB |

_{🤖 This report was automatically generated by heaviest-objects-in-the-universe}

[codecov]

Codecov Report

Attention: Patch coverage is 83.33333% with 1 line in your changes missing coverage. Please review.

Project coverage is 80.92%. Comparing base (6b97186) to head (7a928f5).

Files with missing lines	Patch %	Lines
packages/dd-trace/src/plugins/index.js	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5272      +/-   ##
==========================================
- Coverage   81.24%   80.92%   -0.33%     
==========================================
  Files         487      480       -7     
  Lines       21703    21531     -172     
==========================================
- Hits        17633    17424     -209     
- Misses       4070     4107      +37     

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[datadog-datadog-prod-us1]

Datadog Report

Branch report: lazy-fetch
Commit report: 4592dc6
Test service: dd-trace-js-integration-tests

✅ 0 Failed, 627 Passed, 0 Skipped, 14m 44.5s Total Time

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-02-14 08:51:10

Comparing candidate commit 7a928f5 in PR branch lazy-fetch with baseline commit 6b97186 in branch master.

Found 0 performance improvements and 12 performance regressions! Performance is the same for 896 metrics, 25 unstable metrics.

scenario:appsec-iast-startup-time-iast-enabled-18

• 🟥 cpu_user_time [+95.381ms; +121.248ms] or [+5.466%; +6.948%]
• 🟥 execution_time [+108.549ms; +128.490ms] or [+5.638%; +6.674%]

scenario:appsec-iast-startup-time-iast-enabled-20

• 🟥 cpu_user_time [+99.831ms; +125.403ms] or [+5.570%; +6.996%]
• 🟥 execution_time [+112.771ms; +134.788ms] or [+5.564%; +6.650%]
• 🟥 max_rss_usage [+7.013MB; +8.649MB] or [+5.217%; +6.434%]

scenario:appsec-iast-with-vulnerability-iast-enabled-always-active-18

• 🟥 cpu_user_time [+113.063ms; +151.558ms] or [+6.284%; +8.423%]

scenario:appsec-iast-with-vulnerability-iast-enabled-always-active-20

• 🟥 cpu_user_time [+96.661ms; +129.730ms] or [+5.336%; +7.162%]

scenario:appsec-iast-with-vulnerability-iast-enabled-default-config-18

• 🟥 cpu_user_time [+135.338ms; +171.084ms] or [+8.077%; +10.211%]
• 🟥 execution_time [+126.540ms; +213.450ms] or [+5.080%; +8.569%]

scenario:appsec-iast-with-vulnerability-iast-enabled-default-config-20

• 🟥 cpu_user_time [+87.039ms; +117.262ms] or [+5.112%; +6.887%]

scenario:startup-with-tracer-22

• 🟥 cpu_user_time [+14.040ms; +22.532ms] or [+7.457%; +11.967%]
• 🟥 execution_time [+20.698ms; +22.087ms] or [+8.990%; +9.593%]