Preliminary tests for Load tasks

Why these changes are being introduced:

Load tasks will upsert data into Quickbase.  Before any actual Load Tasks
exist in this project, we have enough of a framework to create some tests
that simulate what Load Tasks will look like and test them a bit.

How this addresses that need:
* Creates tests in tests/test_load.py that sketch Load Tasks behavior

Side effects of this change:
* None

Relevant ticket(s):
* https://mitlibraries.atlassian.net/browse/HRQB-12

tests/test_load.py

@@ -0,0 +1,49 @@
+# ruff: noqa: N803
+
+import pytest
+
+from hrqb.base import QuickbaseUpsertTask
+
+
+def test_load_upsert_records_default_get_records_no_parent_error(
+    tmpdir,
+    mocked_table_name,
+):
+    task = QuickbaseUpsertTask(
+        path=f"{tmpdir}/load__example_table_0.json",
+        table_name=mocked_table_name,
+    )
+    with pytest.raises(
+        ValueError, match="Expected a single input to this Task but found: 0"
+    ):
+        task.get_records()
+
+
+def test_load_upsert_records_default_get_records_returns_dict(
+    tmpdir,
+    quickbase_load_task_with_parent_data,
+    mocked_table_name,
+    mocked_upsert_data,
+):
+    task = quickbase_load_task_with_parent_data(
+        path=f"{tmpdir}/load__example_table_0.json",
+        table_name=mocked_table_name,
+    )
+    assert task.get_records() == mocked_upsert_data
+
+
+def test_load_upsert_records_task_run_success(
+    tmpdir,
+    quickbase_load_task_with_parent_data,
+    mocked_table_name,
+    mocked_qb_api_getAppTables,
+    mocked_qb_api_upsert,
+):
+
+    task = quickbase_load_task_with_parent_data(
+        path=f"{tmpdir}/load__example_table_0.json",
+        table_name=mocked_table_name,
+    )
+    task.run()
+    assert task.complete()
+    assert task.output().read() == mocked_qb_api_upsert