feat: login credential provider

[stobrien89]

Description of changes:
Adds LoginCredentialProvider, which supports AWS Console sign-in credentials through the aws login CLI workflow.

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[stobrien89]

Integ:

vendor/bin/behat --format=progress --tags=integ
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Smoke:

vendor/bin/behat --format=progress --suite=smoke --tags='~@noassumerole'
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