Rearrange pp_versioned_models test

[gshank]

resolves #7781

Problem

The partial_parsing test TestVersionedModels was intermittently failing, from 1 to 3 times per 500 runs. From the logs from the failing test runs it appeared to happen in the view materialization macro when "existing_relation" was retrieved from "load_cached_relation" but no longer existed by the time the rename was done later:

  {% if existing_relation is not none %}
    {{ adapter.rename_relation(existing_relation, backup_relation) }}

This is probably a race condition or something similar, and might possibly be due to the testing environment.

Solution

I separated out the test that was failing into its own file, test_versioned_models.py and refactored a bit to avoid using "run_dbt_and_capture" which was making it harder to read the test output. This doesn't address any possibly underlying race condition, but so far the failure has not occurred with the flaky_test workflow. The test is commented so that if such an error occurs again, we could reduce the window for the race condition.

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

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (main@867534c). Click here to learn what that means.
The diff coverage is n/a.

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[MichelleArk]

Should we backport to 1.5 and 1.6 to avoid breaking automated workflows (e.g: https://dbt-labs.slack.com/archives/C02MC5GKCKX/p1689798984364629)?

[gshank]

Yeah, we can do that. It's isolated to tests so ought to be okay.

[github-actions]

The backport to 1.5.latest failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-1.5.latest 1.5.latest
# Navigate to the new working tree
cd .worktrees/backport-1.5.latest
# Create a new branch
git switch --create backport-8150-to-1.5.latest
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 a32713198bcafa526b50fca6cd7b1e1a2c2813ec
# Push it to GitHub
git push --set-upstream origin backport-8150-to-1.5.latest
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-1.5.latest

Then, create a pull request where the base branch is 1.5.latest and the compare/head branch is backport-8150-to-1.5.latest.