Examples or documentation for "WHERE field IN $1" - should be "WHERE field IN ($1)"

**Is your feature request related to a problem? Please describe.**
I ran into a hard-to-debug situation with a query like the following:
```
roleAssignmentUuids := []string{"a-a-a", "b-b-b"}
queryStr := `
SELECT stuff FROM table
WHERE role_assignment_id IN $1;`
// this is wrong, it only works when you use ($1)
rows, err := client.Query(ctx, queryStr, roleAssignmentUuids)
```
**Describe the solution you'd like**
Provide an example in `examples/` that demonstrates the correct placeholder usage in this case.

**Describe alternatives you've considered**
An alternative would be to prevent against this case in code, but, eh.

Start by reviewing the existing examples/ directory and the issue's Go query example. Add an example showing the correct PostgreSQL placeholder syntax for an array passed to IN, including parentheses around $1. Done means the example clearly contrasts the incorrect and correct forms.

Written by the indexing model from the issue text.