Lowercase column names by default

[dbeatty10]

resolves #254

Problem

Macros that generate unit tests are capitalizing non-quoted column names for Snowflake.

Solution

Lowercase all column names by default.
Defer to #255 to handle case-sensitive column names.

Checklist

• This code is associated with an issue which has been triaged and accepted for development.
• 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
• I have updated the README.md (if applicable)

[dbeatty10]

I don't understand why, but I'm getting different results for tests running in CircleCI vs. GitHub Actions:

CircleCI:

GitHub Actions:

There aren't any caches here or here:

[dbeatty10]

When I ran the integration changes locally without the change in this PR, they failed, But they succeeded once I made this change. So the GitHub Actions failure is an anomaly out of those 3 different methods to execute the integration tests. Since
we want this change, I'm going to merge anyways even I though I haven't figured out reason for the GHA failures 🤷.