test: move prepared statements config related tests to spec tests

Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>

test/io/__snapshots__/test_cli/test_schema_cache_snapshot[dbRoutines].yaml

@@ -512,23 +512,6 @@
       pdSchema: public
       pdVolatility: Volatile
 
-- - qiName: uses_prepared_statements
-    qiSchema: public
-  - - pdDescription: null
-      pdFuncSettings: []
-      pdHasVariadic: false
-      pdName: uses_prepared_statements
-      pdParams: []
-      pdReturnType:
-        contents:
-          contents:
-            qiName: bool
-            qiSchema: pg_catalog
-          tag: Scalar
-        tag: Single
-      pdSchema: public
-      pdVolatility: Volatile
-
 - - qiName: repeatable_read_isolation_level
     qiSchema: public
   - - pdDescription: null

test/io/fixtures/schema.sql

@@ -54,10 +54,6 @@ create function v1.get_guc_value(name text) returns text as $$
   select nullif(current_setting(name), '')::text;
 $$ language sql;
 
-create function uses_prepared_statements() returns bool as $$
-  select count(name) > 0 from pg_catalog.pg_prepared_statements
-$$ language sql;
-
 create function change_max_rows_config(val int, notify bool default false) returns void as $_$
 begin
   execute format($$

test/io/test_io.py

@@ -420,27 +420,6 @@ def test_notify_do_nothing(defaultenv):
         assert output == []
 
 
-def test_db_prepared_statements_enable(defaultenv):
-    "Should use prepared statements when the setting is enabled."
-
-    with run(env=defaultenv) as postgrest:
-        response = postgrest.session.post("/rpc/uses_prepared_statements")
-        assert response.text == "true"
-
-
-def test_db_prepared_statements_disable(defaultenv):
-    "Should not use any prepared statements when the setting is disabled."
-
-    env = {
-        **defaultenv,
-        "PGRST_DB_PREPARED_STATEMENTS": "false",
-    }
-
-    with run(env=env) as postgrest:
-        response = postgrest.session.post("/rpc/uses_prepared_statements")
-        assert response.text == "false"
-
-
 def test_statement_timeout(defaultenv, metapostgrest):
     "Statement timeout times out slow statements"