fix: Support multi-argument version of unnest

Currently, `sqlc` errors out when it encounters the multi-argument
version of the `UNNEST` function. This is because the function is not
marked as variadic. Instead, the argument type is defined as
[`anymultirange`](https://www.postgresql.org/docs/current/extend-type-system.html#EXTEND-TYPES-POLYMORPHIC).

Fixes #3507

Signed-off-by: Charith Ellawala <[email protected]>

Author: charithe

internal/endtoend/testdata/unnest_multiple/postgresql/pgx/v4/go/db.go

@@ -0,0 +1,9 @@
+-- name: CreateMemories :many
+INSERT INTO memories (vampire_id, memory, victim)
+SELECT
+    unnest(@vampires::uuid[], @memories::text[], @victims::text[])
+RETURNING
+    *;
+
+-- name: GetMemories :many
+SELECT vampires.id::uuid, vampires.memory::text, vampires.victim::text FROM unnest(@vampires::uuid[], @memories::text[], @victims::text[]) AS vampires (id, memory, victim);

internal/endtoend/testdata/unnest_multiple/postgresql/pgx/v4/go/models.go

@@ -0,0 +1,12 @@
+CREATE TABLE vampires (
+    id uuid PRIMARY KEY DEFAULT gen_random_uuid ()
+);
+
+CREATE TABLE memories (
+    id uuid PRIMARY KEY DEFAULT gen_random_uuid (),
+    vampire_id uuid REFERENCES vampires (id) NOT NULL,
+    memory text NOT NULL,
+    victim text NOT NULL,
+    created_at timestamp NOT NULL DEFAULT NOW(),
+    updated_at timestamp
+);

internal/endtoend/testdata/unnest_multiple/postgresql/pgx/v4/go/querier.go

@@ -0,0 +1,14 @@
+{
+  "version": "1",
+  "packages": [
+    {
+      "path": "go",
+      "engine": "postgresql",
+      "sql_package": "pgx/v4",
+      "name": "querytest",
+      "schema": "schema.sql",
+      "queries": "query.sql",
+      "emit_interface": true
+    }
+  ]
+}