awsprometheusremotewrite: Add support for given IAM roles

[bonclay7]

Description:
Adding to the aws prometheus exporter the possibility to assume a role to unlock cross account scenarios

Link to tracking Issue: #2654

Testing:
Added some unit tests to cover the new parameter by running make
Ran the collector using make run with a config to test the changes

Config

receivers:
  prometheus:
    config:
      global:
        scrape_interval: 15s
        scrape_timeout: 10s
      scrape_configs:
      - job_name: "prometheus-demo-app"
        static_configs:
        - targets: [ 0.0.0.0:8888 ]

exporters:
  awsprometheusremotewrite:
    endpoint: https://aps-workspaces.eu-west-1.amazonaws.com/workspaces/<ws_id>/api/v1/remote_write
    aws_auth:
      region: eu-west-1
      service: "aps"
      role_arn: "arn:aws:iam::account:role/role_name"
  logging:
    loglevel: debug
extensions:
  health_check:
  pprof:
    endpoint: :1888
  zpages:
    endpoint: :55679

service:
  extensions: [pprof, zpages, health_check]
  pipelines:
    metrics:
      receivers: [prometheus]
      exporters: [logging, awsprometheusremotewrite]

With metrics successfully being sent to the destination

Documentation:
Configuration option

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ Rodrigue Koffi (3cf3439, 5059b56, 62ca64e)

[codecov]

Codecov Report

Merging #2675 (4644921) into main (7c28ef1) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #2675      +/-   ##
==========================================
+ Coverage   91.40%   91.43%   +0.02%     
==========================================
  Files         435      435              
  Lines       21626    21630       +4     
==========================================
+ Hits        19768    19778      +10     
+ Misses       1391     1388       -3     
+ Partials      467      464       -3     

Flag	Coverage Δ
integration	69.18% <ø> (ø)
unit	90.34% <100.00%> (+0.02%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
exporter/awsprometheusremotewriteexporter/auth.go	86.36% <100.00%> (+10.75%)	⬆️
...porter/awsprometheusremotewriteexporter/factory.go	100.00% <100.00%> (ø)
receiver/k8sclusterreceiver/watcher.go	97.64% <0.00%> (+2.35%)	⬆️

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[bogdandrutu]

Please be nice with codecov :)

[bonclay7]

Hi @bogdandrutu, I've tried !