fix(codegen/golang): Don't import "strings" for sqlc.slice() with pgx (#3073)

Also fix the invalid test that should have caught this

Resolves #3065

Author: andrewmbenton

internal/codegen/golang/imports.go

@@ -390,7 +390,7 @@ func (i *importer) queryImports(filename string) fileImports {
 	}
 
 	sqlpkg := parseDriver(i.Options.SqlPackage)
-	if sqlcSliceScan() {
+	if sqlcSliceScan() && !sqlpkg.IsPGX() {
 		std["strings"] = struct{}{}
 	}
 	if sliceScan() && !sqlpkg.IsPGX() {

internal/endtoend/testdata/sqlc_slice/postgresql/pgx/go/models.go

@@ -1,5 +1,7 @@
 -- name: FuncParamIdent :many
-SELECT name FROM foo WHERE name = sqlc.arg(slug);
+SELECT name FROM foo WHERE name = sqlc.arg(slug)
+  AND id IN (sqlc.slice(favourites));
 
 -- name: FuncParamString :many
-SELECT name FROM foo WHERE name = sqlc.arg('slug');
+SELECT name FROM foo WHERE name = sqlc.arg('slug')
+  AND id IN (sqlc.slice('favourites'));

internal/endtoend/testdata/sqlc_slice/postgresql/pgx/go/query.sql.go

@@ -1,2 +1,2 @@
-CREATE TABLE foo (name text not null);
+CREATE TABLE foo (id int not null, name text not null);