manual update of version to 1.8.0 final, and batch changelog

[McKnight-42]

resolves #
docs dbt-labs/docs.getdbt.com/#

Problem

manually updating the version number and compiling changlog

Solution

Checklist

• I have read the contributing guide and understand what's expected of me
• I have run this code in development and it appears to resolve the stated issue
• This PR includes tests, or tests are not required/relevant for this PR
• This PR has no interface changes (e.g. macros, cli, logs, json artifacts, config files, adapter interface, etc) or this PR has already received feedback and approval from Product or DX

[mikealfare]

This is failing on irrelevant tests that should be removed. In the interest of time, this will be merged and a separate PR will address removing the tests.