chore: upgrade dev and doc dependencies

[honglu]

Description of changes:

• Update dev dependency pyyaml to newer version
• Update doc dependencies requests and urllib3 to newer version

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov-io]

Codecov Report

Merging #811 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #811   +/-   ##
=======================================
  Coverage   94.32%   94.32%           
=======================================
  Files          67       67           
  Lines        2626     2626           
  Branches      464      464           
=======================================
  Hits         2477     2477           
  Misses         78       78           
  Partials       71       71

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