fix: SQLAlchemy subquery and cache warnings

Author: hrideshmg

database.py

@@ -163,6 +163,8 @@ def db_type(cls) -> DeclEnumType:
 class DeclEnumType(SchemaType, TypeDecorator):
     """Declarative enumeration type."""
 
+    cache_ok = True
+
     def __init__(self, enum: Any) -> None:
         self.enum = enum
         self.impl = Enum(

mod_ci/controllers.py

@@ -224,9 +224,9 @@ def gcp_instance(app, db, platform, repository, delay) -> None:
 
     finished_tests = db.query(TestProgress.test_id).filter(
         TestProgress.status.in_([TestStatus.canceled, TestStatus.completed])
-    ).subquery()
+    )
 
-    running_tests = db.query(GcpInstance.test_id).subquery()
+    running_tests = db.query(GcpInstance.test_id)
 
     pending_tests = Test.query.filter(
         Test.id.notin_(finished_tests), Test.id.notin_(running_tests), Test.platform == platform