don't trace profiler export

[bengl]

What does this PR do?

Adds a no-op context around HTTP calls made by the profiling exporter.

Motivation

HTTP calls initiated by this library should not be traced.

[codecov]

Codecov Report

Merging #2600 (61fbb1d) into master (23828d6) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2600   +/-   ##
=======================================
  Coverage   89.71%   89.71%           
=======================================
  Files         293      293           
  Lines        9993     9997    +4     
=======================================
+ Hits         8965     8969    +4     
  Misses       1028     1028           

Impacted Files	Coverage Δ
packages/dd-trace/src/profiling/exporters/agent.js	98.71% <100.00%> (+0.06%)	⬆️

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[pr-commenter]

Benchmarks

Comparing candidate commit 61fbb1d in PR branch bengl/no-tracing-profiler-export with baseline commit 23828d6 in branch master.

Found 2 performance improvements and 7 performance regressions! Performance is the same for 957 cases.

scenario:appsec-control-14

• 🟥 cpu_user_time [+5.674ms; +11.730ms] or [+2.289%; +4.732%]
• 🟥 execution_time [+4.719ms; +9.621ms] or [+1.610%; +3.282%]
• 🟩 max_rss_usage [-0.968KB; -0.855KB] or [-2.036%; -1.798%]

scenario:appsec-control-with-attacks-14

• 🟥 cpu_user_time [+4.016ms; +9.803ms] or [+1.600%; +3.907%]
• 🟥 execution_time [+7.486ms; +11.026ms] or [+2.561%; +3.772%]

scenario:plugin-bluebird-with-tracer-14

• 🟥 cpu_user_time [+5.316ms; +8.583ms] or [+2.336%; +3.771%]
• 🟥 execution_time [+8.431ms; +8.821ms] or [+3.328%; +3.482%]
• 🟥 max_rss_usage [+0.877KB; +0.911KB] or [+1.682%; +1.747%]

scenario:plugin-q-with-tracer-18

• 🟩 instructions [-31209501; -23078534] or [-2.095%; -1.549%]