Adding PDT region account for 1p algorithms

[ericangelokim]

Added PDT Account ID to Amazon Estimator.

Note: LDA is missing because we won't be deployed to LDA by launch date due to infrastructure problems. Will be working on this after initial launch.

Note: My commits are a little funky, I didn't realize the Pull Request I made to sync my fork to aws/master would create a new commit.

Merge Checklist

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• I have read the CONTRIBUTING doc
• [ x] I have added tests that prove my fix is effective or that my feature works (if appropriate)
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[codecov-io]

Codecov Report

Merging #391 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #391   +/-   ##
=======================================
  Coverage   93.42%   93.42%           
=======================================
  Files          52       52           
  Lines        3665     3665           
=======================================
  Hits         3424     3424           
  Misses        241      241

Impacted Files	Coverage Δ
src/sagemaker/amazon/amazon_estimator.py	88.72% <ø> (ø)	⬆️

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