Document how to use types with the AJS snippet

[juliofarah]

Description

This PR updates AJS Core README to include documentation on how to use types when using the AJS Snippet

Test plan

Testing not required because this is only a documentation change.

Release plan

New version is not required because this is only a documentation change.

[pooyaj]

💥

[codecov-commenter]

Codecov Report

❗ No coverage uploaded for pull request base (master@45256be). Click here to learn what that means.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #179   +/-   ##
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  Coverage          ?   96.36%           
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  Files             ?        3           
  Lines             ?       55           
  Branches          ?        0           
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  Hits              ?       53           
  Misses            ?        2           
  Partials          ?        0           

Impacted Files	Coverage Δ
lib/utils/each.js	90.47% <0.00%> (ø)
lib/utils/map.js	100.00% <0.00%> (ø)
lib/utils/clone.js	100.00% <0.00%> (ø)

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