Revert "add documentation for secrets manager"

[duncanista]

This reverts commit 6eaad050af0552847d6dc87fc5aeb584d6a07ea3.

What does this PR do?

Remove the docs for Secrets Manager until we release the new version of macro.

Motivation

DataDog/datadog-cloudformation-macro/issues#53.

Testing Guidelines

N/A

Additional Notes

Types of changes

• [ ] Bug fix
• [ ] New feature
• [ ] Breaking change
• [x] Misc (docs, refactoring, dependency upgrade, etc.)

Check all that apply

• [ ] This PR's description is comprehensive
• [ ] This PR contains breaking changes that are documented in the description
• [ ] This PR introduces new APIs or parameters that are documented and unlikely to change in the foreseeable future
• [ ] This PR impacts documentation, and it has been updated (or a ticket has been logged)
• [ ] This PR's changes are covered by the automated tests
• [ ] This PR collects user input/sensitive content into Datadog

[codecov-commenter]

Codecov Report

Merging #54 (bf62241) into master (65e2138) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #54   +/-   ##
=======================================
  Coverage   90.39%   90.39%           
=======================================
  Files           7        7           
  Lines         479      479           
  Branches      108      108           
=======================================
  Hits          433      433           
  Misses         22       22           
  Partials       24       24           

---

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 65e2138...bf62241. Read the comment docs.