ADAP-1260: [Bug] [dbt-redshift] merge macro aliases cause Redshift materializations to fail

### Is this a new bug?

- [x] I believe this is a new bug
- [x] I have searched the existing issues, and I could not find an existing issue for this bug

### Which packages are affected?

- [ ] dbt-adapters
- [ ] dbt-tests-adapter
- [ ] dbt-athena
- [ ] dbt-athena-community
- [ ] dbt-bigquery
- [ ] dbt-postgres
- [x] dbt-redshift
- [ ] dbt-snowflake
- [ ] dbt-spark

### Current Behavior

After #910 our incremental Redshift loads started failing due to an alias syntax error (Redshift doesnt allow aliases in some DELETE/INSERT jobs)

[DBT slack thread](https://getdbt.slack.com/archives/CJARVS0RY/p1743469802292739)

### Expected Behavior

Incremental models should execute their delete/insert steps without issue

### Steps To Reproduce

On `dbt-adapters==1.14.4` , try a Redshift incremental delete/insert model and see if you get this error

When you change to an easier version of the repo it should work fine:
`dbt-adapters==1.14.3`

### Relevant log output

```shell
Example Airflow error
Database Error in model
[2025-04-01, 00:55:29 UTC] {subprocess.py:93} INFO - syntax error at or near "as" in context "from "analytics"."schema_name"."example_redshift_table_name" as", at line 6, column 80

Where we think the "Redshift doesnt like aliases in Delete From" issue is arising
delete from "analytics"."schema_name"."example_redshift_table_name" as DBT_INTERNAL_DEST
where (composite_key) in (
select distinct composite_key
from "table_name__dbt_tmp235413576120" as DBT_INTERNAL_SOURCE
);
```

### Environment

```markdown
- dbt-adapters==1.14.4
```

### Additional Context

_No response_