Resolve "Remove nose.tools dependency"

Summary

This MR removes nose from the integration tests (related to #23 (closed)).

Focus

Test Environment

Regular integration tests

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• Reference related issues
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• I understand the intent of this MR
• All automated tests pass
• Up-to-date CHANGELOG.md (or not necessary)
• Appropriate user and developer documentation (or not necessary)
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tests/test_query_template.py

@@ -25,11 +25,22 @@
 
 @author: tf
 """
-import caosdb as db
-from nose.tools import assert_true, assert_equal, assert_is_not_none
+import linkahead as db
 from pytest import raises
 
 
+def assert_true(a):
+    assert a
+
+
+def assert_equal(a, b):
+    assert a == b
+
+
+def assert_is_not_none(a):
+    assert a is not None
+
+
 def setup_module():
     db.configure_connection()
     try:
@@ -342,12 +353,12 @@ def test_query_with_subquery_referenced_by():
             unique=True).name,
         "TestRecord")
 
-    assert_true(
+    assert_equal(
         db.execute_query(
             "FIND TestPerson WHICH IS REFERENCED BY TestPigExperiment AS A TestConductor",
             unique=True).name,
         "TestJohnDoe")
-    assert_true(
+    assert_equal(
         db.execute_query(
             "FIND TestPerson WHICH IS REFERENCED BY TestPigExperiment",
             unique=True).name,