docs(readme): update link to developer documentation

[BondAnthony]

This will update the link to the developer documentation github pages.

Is this a bug fix or adding new feature?
Fixing a readme broken link

What is this PR about? / Why do we need it?
Documentation

What testing is done?
Confirmed the link doesn't return a 404.

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[coveralls]

Pull Request Test Coverage Report for Build 1311

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 81.253%

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Totals
Change from base Build 1304:	0.0%
Covered Lines:	1595
Relevant Lines:	1963

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💛 - Coveralls

[wongma7]

/lgtm
/approve
thank you

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: BondAnthony, wongma7

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