docs(feature-flags): correct link and json examples

[michaelbrewer]

Issue #, if available:

Description of changes:

Minimal doc fixes for feature toggles link and json examples

Checklist

• Meet tenets criteria
• Update tests
• Update docs
• PR title follows conventional commit semantics

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[michaelbrewer]

@heitorlessa minimal version of #603

[codecov-commenter]

Codecov Report

Merging #605 (25d9c62) into develop (f627b02) will decrease coverage by 0.04%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           develop     #605      +/-   ##
===========================================
- Coverage    99.95%   99.91%   -0.05%     
===========================================
  Files          113      113              
  Lines         4535     4535              
  Branches       246      246              
===========================================
- Hits          4533     4531       -2     
- Misses           0        1       +1     
- Partials         2        3       +1     

Impacted Files	Coverage Δ
aws_lambda_powertools/utilities/parser/types.py	71.42% <0.00%> (-28.58%)	⬇️

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