Make MAXIMUM_SEED_SIZE configurable

[acurtis-evi]

resolves #7117

Description

Use DBT_MAXIMUM_SEED_SIZE as an optional env variable to set the size

Checklist

• I have read the contributing guide and understand what's expected of me
• I have signed the CLA
• 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 opened an issue to add/update docs, or docs changes are not required/relevant for this PR
• I have run changie new to create a changelog entry

[jtcohen6]

@acurtis-evi Thanks for the PR! Could you open an issue, and link back to the Slack thread for context?

[acurtis-evi]

Realize this is fairly simple, but it would help my team!

[dbeatty10]

@acurtis-evi Yeah! Thanks for opening this PR 🏆

I made a small update to the PR description to get the PR to link with the issue properly.

Before:

resolves #

https://github.com/dbt-labs/dbt-core/issues/7117

After:

resolves https://github.com/dbt-labs/dbt-core/issues/7117

[acurtis-evi]

I'm going to close this PR in favor of working with Noah on PR #7125