Add client ip parsing and reporting

[simon-id]

What does this PR do?

Add a parsing algorithm to heuristically find the real client ip from headers when behind a proxy, and report it by default. Also add an env var to force which header should the IP be sourced from.

Motivation

AppSec backend WAF and APM tags unification.

[codecov[bot]]

Codecov Report

Merging #2166 (d0f239b) into master (ada0716) will increase coverage by 0.02%. The diff coverage is 90.74%.

@@            Coverage Diff             @@
##           master    #2166      +/-   ##
==========================================
+ Coverage   92.70%   92.73%   +0.02%     
==========================================
  Files         224      227       +3     
  Lines        8718     8819     +101     
==========================================
+ Hits         8082     8178      +96     
- Misses        636      641       +5     

Impacted Files	Coverage Δ
packages/dd-trace/src/plugins/util/ip_blocklist.js	44.44% <44.44%> (ø)
packages/dd-trace/src/config.js	99.02% <100.00%> (+0.03%)	:arrow_up:
packages/dd-trace/src/plugin_manager.js	100.00% <100.00%> (ø)
packages/dd-trace/src/plugins/util/web.js	92.06% <100.00%> (+1.15%)	:arrow_up:
packages/dd-trace/src/ritm.js	87.65% <0.00%> (-0.66%)	:arrow_down:
packages/dd-trace/src/iitm.js	100.00% <0.00%> (ø)
packages/dd-trace/src/exporters/common/request.js	96.55% <0.00%> (ø)
packages/dd-trace/src/telemetry.js
packages/dd-trace/src/telemetry/send-data.js	100.00% <0.00%> (ø)
packages/dd-trace/src/telemetry/index.js	95.91% <0.00%> (ø)
... and 1 more

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[simon-id]

I got a review from Ugaitz but I'd still like your eyes @rochdev

[github-actions[bot]]

Overall package size

Self size: 2.64 MB Deduped: 30.27 MB No deduping: 30.92 MB

Dependency sizes

name	version	self size	total size
@datadog/pprof	1.0.2	8.74 MB	14.46 MB
@datadog/native-metrics	1.4.2	6.61 MB	7.04 MB
@datadog/native-appsec	1.2.1	5.1 MB	5.43 MB
cidr-matcher	2.1.1	224.94 kB	451.39 kB
opentracing	0.14.7	194.81 kB	194.81 kB
@datadog/sketches-js	2.0.0	105.44 kB	105.44 kB
lodash.sortby	4.7.0	75.76 kB	75.76 kB
semver	5.7.1	61.58 kB	61.58 kB
ignore	5.2.0	48.87 kB	48.87 kB
import-in-the-middle	1.3.1	30.44 kB	34.91 kB
istanbul-lib-coverage	3.2.0	29.34 kB	29.34 kB
retry	0.10.1	27.44 kB	27.44 kB
lodash.uniq	4.5.0	25.01 kB	25.01 kB
limiter	1.1.5	23.17 kB	23.17 kB
lodash.kebabcase	4.1.1	17.75 kB	17.75 kB
lodash.pick	4.4.0	16.33 kB	16.33 kB
crypto-randomuuid	1.0.0	11.18 kB	11.18 kB
diagnostics_channel	1.1.0	7.07 kB	7.07 kB
path-to-regexp	0.1.7	6.78 kB	6.78 kB
koalas	1.0.2	6.47 kB	6.47 kB
methods	1.1.2	5.29 kB	5.29 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}