builtins: change pg_column_size() to accepts arguments of types.Any

Previously, pg_column_size() required that all arguments have the same
type. This patch removes that restriction so that every argument can
have a different type.

Epic: none
Release note (sql change): pg_column_size() no longer requires that all
arguments have the same type.

Author: mw5h

docs/generated/sql/functions.md

@@ -3500,7 +3500,7 @@ may increase either contention or retry errors, or both.</p>
 </span></td><td>Stable</td></tr>
 <tr><td><a name="pg_column_is_updatable"></a><code>pg_column_is_updatable(reloid: oid, attnum: int2, include_triggers: <a href="bool.html">bool</a>) &rarr; <a href="bool.html">bool</a></code></td><td><span class="funcdesc"><p>Returns whether the given column can be updated.</p>
 </span></td><td>Stable</td></tr>
-<tr><td><a name="pg_column_size"></a><code>pg_column_size(anyelement...) &rarr; <a href="int.html">int</a></code></td><td><span class="funcdesc"><p>Return size in bytes of the column provided as an argument</p>
+<tr><td><a name="pg_column_size"></a><code>pg_column_size(any...) &rarr; <a href="int.html">int</a></code></td><td><span class="funcdesc"><p>Return size in bytes of the column provided as an argument</p>
 </span></td><td>Stable</td></tr>
 <tr><td><a name="pg_function_is_visible"></a><code>pg_function_is_visible(oid: oid) &rarr; <a href="bool.html">bool</a></code></td><td><span class="funcdesc"><p>Returns whether the function with the given OID belongs to one of the schemas on the search path.</p>
 </span></td><td>Stable</td></tr>

pkg/sql/sem/builtins/fixed_oids.go

@@ -1497,7 +1497,7 @@ var builtinOidsArray = []string{
 	1526: `inet_client_port() -> int`,
 	1527: `inet_server_addr() -> inet`,
 	1528: `inet_server_port() -> int`,
-	1529: `pg_column_size(anyelement...) -> int`,
+	1529: `pg_column_size(any...) -> int`,
 	1530: `information_schema._pg_truetypid(pg_attribute: tuple, pg_type: tuple) -> oid`,
 	1531: `information_schema._pg_truetypmod(pg_attribute: tuple, pg_type: tuple) -> int4`,
 	1532: `information_schema._pg_char_max_length(typid: oid, typmod: int4) -> int`,

pkg/sql/sem/builtins/pg_builtins.go

@@ -2044,7 +2044,7 @@ var pgBuiltins = map[string]builtinDefinition{
 	"pg_column_size": makeBuiltin(defProps(),
 		tree.Overload{
 			Types: tree.VariadicType{
-				VarType: types.AnyElement,
+				VarType: types.Any,
 			},
 			ReturnType: tree.FixedReturnType(types.Int),
 			Fn: func(_ context.Context, _ *eval.Context, args tree.Datums) (tree.Datum, error) {