[ses] Add 'XExistsTemplate' API

[evalphobia]

No description provided.

[codecov-commenter]

Codecov Report

Merging #35 (b856330) into master (ccccae3) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #35   +/-   ##
=======================================
  Coverage   14.37%   14.37%           
=======================================
  Files          57       57           
  Lines        3074     3074           
=======================================
  Hits          442      442           
  Misses       2475     2475           
  Partials      157      157           

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update ccccae3...b856330. Read the comment docs.

[evalphobia]

Note: https://github.com/evalphobia/aws-sdk-go-v2-wrapper/releases/tag/v0.3.6