increase delta for fastapi flaky test (open-telemetry#2591)

Author: emdneto

instrumentation/opentelemetry-instrumentation-fastapi/tests/test_fastapi_instrumentation.py

@@ -254,7 +254,7 @@ def test_basic_metric_success(self):
                         dict(point.attributes),
                     )
                     self.assertEqual(point.count, 1)
-                    self.assertAlmostEqual(duration, point.sum, delta=30)
+                    self.assertAlmostEqual(duration, point.sum, delta=40)
                 if isinstance(point, NumberDataPoint):
                     self.assertDictEqual(
                         expected_requests_count_attributes,
@@ -279,7 +279,7 @@ def test_basic_post_request_metric_success(self):
                 if isinstance(point, HistogramDataPoint):
                     self.assertEqual(point.count, 1)
                     if metric.name == "http.server.duration":
-                        self.assertAlmostEqual(duration, point.sum, delta=30)
+                        self.assertAlmostEqual(duration, point.sum, delta=40)
                     elif metric.name == "http.server.response.size":
                         self.assertEqual(response_size, point.sum)
                     elif metric.name == "http.server.request.size":