Add integration test for derived metrics with shared aliases

This commit adds a new integration test that uses
`derived_sharedalias_1a` and `derived_sharedalias_2`.

I manually optimized the SQL from the output of the optimized SQL
snapshot.

tests_metricflow/integration/test_cases/itest_metrics.yaml

@@ -551,6 +551,22 @@ integration_test:
         ds
     ) a
 ---
+# TODO @serramatutu: I WAS HERE
+integration_test:
+  name: shared_alias_derived_metric
+  description: Tests derived metrics which use the same alias for different things
+  model: SIMPLE_MODEL
+  metrics: ["derived_sharedalias_1a", "derived_sharedalias_2"]
+  group_bys: ["booking__is_instant"]
+  check_query: |
+    SELECT
+      is_instant AS booking__is_instant
+      , COUNT(*) - 10 AS derived_sharedalias_1a
+      , SUM(CASE WHEN is_instant THEN 1 ELSE 0 END) + 10 AS derived_sharedalias_2
+    FROM {{ source_schema }}.fct_bookings
+    GROUP BY
+      booking__is_instant
+---
 integration_test:
   name: two_metrics_with_null_dimension_values
   description: Tests querying two metrics with a dimension having a NULL values