update user docs-issue workflow

[McKnight-42]

https://github.com/dbt-labs/adapters-team-private/issues/143

Problem

We want to make sure all adapters have a docs-issue workflow and if it exists currently make sure it is in the same state as the dbt-core workflow to where we trigger off issues now for parity.

Solution

• check if docs-issue exists
• if does update, if doesn't add workflow
• add user docs label if doesn't exist

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