chore: update link to developer documentation install page

[awentzel]

Description

Update to link into start of developer documentation. Currently, this start page/getting started is work in progress.

Motivation & context

When clicking on current link it takes you to the developer documentation main readme. This is great if that readme contains getting started or different documentation. But, on initial load of this page it's the same exact content and this might be confusing to users. They may immediately click away without seeing out other developer documentation. This will temporarily change the link to the install page of documentation.

Issue type checklist

• Chore: A change that does not impact distributed packages.
• Bug fix: A change that fixes an issue, link to the issue above.
• New feature: A change that adds functionality.

Is this a breaking change?

• This change causes current functionality to break.

Process & policy checklist

• I have added tests for my changes.
• I have tested my changes.
• I have updated the project documentation to reflect my changes.
• I have read the CONTRIBUTING documentation and followed the standards for this project.

[codeclimate]

Code Climate has analyzed commit 3c561bc and detected 0 issues on this pull request.

The test coverage on the diff in this pull request is 100.0% (50% is the threshold).

This pull request will bring the total coverage in the repository to 82.6% (0.0% change).

View more on Code Climate.