Add documentation about AWS authentication

[wbeuil]

Q	A
🐛 Bug fix?	no
🚀 New feature?	no
⚠ Deprecations?	no
❌ BC Break	no
🔗 Related issues	#46
❓ Documentation	yes

Description

It is possible to use driftctl with IAM role by defining a named profile.

As per AWS documentation an example could be:

# in ~/.aws/config file
[profile marketingadmin]
role_arn = arn:aws:iam::123456789012:role/marketingadminrole
source_profile = user1
region = eu-west-3 # to avoid overriding AWS_REGION setting

And then:

$ AWS_PROFILE=marketingadmin driftctl scan

[sjourdan]

awesome

[codecov]

Codecov Report

Merging #52 (c3e0bb1) into main (110813b) will increase coverage by 0.06%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main      #52      +/-   ##
==========================================
+ Coverage   66.93%   67.00%   +0.06%     
==========================================
  Files         146      146              
  Lines        3179     3179              
==========================================
+ Hits         2128     2130       +2     
+ Misses        810      809       -1     
+ Partials      241      240       -1     

Impacted Files	Coverage Δ
pkg/parallel_runner.go	74.46% <0.00%> (+4.25%)	⬆️

[moadibfr]

👍