"CREATE TABLE IF NOT EXISTS" results in a false-positive error if table already exists

Take a script like the auto-generated migration history table creation by Entity Framework:

```sql
CREATE TABLE IF NOT EXISTS "__EFMigrationsHistory" (
"MigrationId" character varying(150) NOT NULL,
"ProductVersion" character varying(32) NOT NULL,
CONSTRAINT "PK___EFMigrationsHistory" PRIMARY KEY ("MigrationId")
);
```

This results in a false error if the table actually already exists:

```
psql:/home/runner/work/somethingsomething.sql:5: NOTICE: relation "__EFMigrationsHistory" already exists, skipping
[...]
Error: Error occurred while running action:
Error: error in file: /home/runner/work/somethingsomething.sql
psql:/home/runner/work/somethingsomething.sql:5: NOTICE: relation "__EFMigrationsHistory" already exists, skipping
```

Which subsequently and wrongly fails the build.

The report names no source file or test entry point. Reproduce the Entity Framework migration script with an existing __EFMigrationsHistory table, then trace how the PostgreSQL action handles the NOTICE and verify that this expected notice no longer causes the build to fail.

Scritto dal modello di indicizzazione a partire dal testo della issue.