Changed url from healthcheck.io to healthchecks.io

[Juoper]

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Category: Documentation Typo

Overview
The Link to healtchecks.io was wrong so i changed it to healtchecks.io
Issue Number (if applicable) #00

Code Quality Checklist (Please complete)

• [x ] All changes are backwards compatible
• [ x] All lint checks and tests are passing
• [ x] There are no (new) build warnings or errors
• [x ] (If a new config option is added) Attribute is outlined in the schema and documented
• [x ] (If a new dependency is added) Package is essential, and has been checked out for security or performance
• [ x] Bumps version, if new feature added

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