perf(go-forwarder): benchmarking decoder vs unmarshal on parsing

[ndakkoune]

I needed to propagate information from SQS events in the parsing package and ended up benchmarking the whole package against an unmarshal approach which, besides being way easier to understand, increased performances of all event sources (but slightly decrease for CW).

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goos: darwin
goarch: arm64
cpu: Apple M4 Max
                     │   decoder   │              unmarshal              │
                     │   sec/op    │   sec/op     vs base                │
Parse_CloudWatch-16    283.2n ± 1%   293.6n ± 1%   +3.65% (p=0.000 n=10)
Parse_S3-16            679.6n ± 1%   641.4n ± 1%   -5.63% (p=0.000 n=10)
Parse_SNS_S3-16        3.653µ ± 1%   2.473µ ± 1%  -32.31% (p=0.000 n=10)
Parse_SQS_S3-16        18.41µ ± 1%   15.73µ ± 1%  -14.52% (p=0.000 n=10)
Parse_SQS_SNS_S3-16    28.46µ ± 1%   26.25µ ± 0%   -7.76% (p=0.000 n=10)
Parse_EventBridge-16   4.446µ ± 1%   1.537µ ± 1%  -65.43% (p=0.000 n=10)
geomean                3.433µ        2.581µ       -24.82%

                     │   decoder    │              unmarshal               │
                     │     B/op     │     B/op      vs base                │
Parse_CloudWatch-16     1064.0 ± 0%     400.0 ± 0%  -62.41% (p=0.000 n=10)
Parse_S3-16             1368.0 ± 0%     528.0 ± 0%  -61.40% (p=0.000 n=10)
Parse_SNS_S3-16        5.703Ki ± 0%   1.727Ki ± 0%  -69.73% (p=0.000 n=10)
Parse_SQS_S3-16        34.47Ki ± 0%   14.79Ki ± 0%  -57.09% (p=0.000 n=10)
Parse_SQS_SNS_S3-16    41.58Ki ± 0%   21.51Ki ± 0%  -48.27% (p=0.000 n=10)
Parse_EventBridge-16    5866.0 ± 0%    1000.0 ± 0%  -82.95% (p=0.000 n=10)
geomean                6.341Ki        2.182Ki       -65.58%

                     │   decoder   │             unmarshal              │
                     │  allocs/op  │ allocs/op   vs base                │
Parse_CloudWatch-16    12.000 ± 0%   8.000 ± 0%  -33.33% (p=0.000 n=10)
Parse_S3-16             28.00 ± 0%   12.00 ± 0%  -57.14% (p=0.000 n=10)
Parse_SNS_S3-16        119.00 ± 0%   35.00 ± 0%  -70.59% (p=0.000 n=10)
Parse_SQS_S3-16         656.0 ± 0%   171.0 ± 0%  -73.93% (p=0.000 n=10)
Parse_SQS_SNS_S3-16     846.0 ± 0%   261.0 ± 0%  -69.15% (p=0.000 n=10)
Parse_EventBridge-16   137.00 ± 0%   19.00 ± 0%  -86.13% (p=0.000 n=10)
geomean                 120.4        37.65       -68.72%