Use is_relational check for schema caching (#3716) (#3737)

* Use is_relational check for schema caching

* Fix flake8

* Update changelog

CHANGELOG.md

@@ -5,6 +5,7 @@
 
 ### Fixes
 - Fix for RPC requests that raise a RecursionError when serializing Undefined values as JSON ([#3464](https://github.com/dbt-labs/dbt/issues/3464), [#3687](https://github.com/dbt-labs/dbt/pull/3687))
+- Avoid caching schemas for tests when `store_failures` is not enabled ([#3715](https://github.com/dbt-labs/dbt/issues/3715), [#3716](https://github.com/dbt-labs/dbt/pull/3716))
 
 ### Under the hood
 - Add `build` RPC method, and a subset of flags for `build` task ([#3595](https://github.com/dbt-labs/dbt/issues/3595), [#3674](https://github.com/dbt-labs/dbt/pull/3674))

core/dbt/adapters/base/impl.py

@@ -31,7 +31,6 @@
 from dbt.contracts.graph.manifest import Manifest, MacroManifest
 from dbt.contracts.graph.parsed import ParsedSeedNode
 from dbt.exceptions import warn_or_error
-from dbt.node_types import NodeType
 from dbt.logger import GLOBAL_LOGGER as logger
 from dbt.utils import filter_null_values, executor
 
@@ -310,8 +309,7 @@ def _get_cache_schemas(self, manifest: Manifest) -> Set[BaseRelation]:
             self.Relation.create_from(self.config, node).without_identifier()
             for node in manifest.nodes.values()
             if (
-                node.resource_type in NodeType.executable() and
-                not node.is_ephemeral_model
+                node.is_relational and not node.is_ephemeral_model
             )
         }