XS✔ ◾ Added async checking section to "Checked by" rule

[tiagov8]

cc @matt-goldman @GordonBeeming @kikibianc @Freego1783

1. What triggered this change? (PBI link, Email Subject, conversation + reason, etc)

@adamcogan 's Re: SSW Developers group losing access

2. What was changed?

Added section for async checking

3. Did you do pair or mob programming (list names)?

no

[github-actions]

PR Metrics

✔ Thanks for keeping your pull request small.
✔ Thanks for adding tests.

	Lines
Product Code	-
Test Code	-
Subtotal	-
Ignored Code	8
Total	8

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[github-actions]

Hi @tiagov8,

We found some markdown suggestions for your Pull Request:

File	Error	Rule
rules/checked-by-xxx/rule.md	Line 57: pipe style	Rule MD055
rules/checked-by-xxx/rule.md	Line 57: pipe style	Rule MD055
rules/checked-by-xxx/rule.md	Line 57: column count	Rule MD056

Please review and update your Markdown files accordingly.