diff --git a/squad/core/comparison.py b/squad/core/comparison.py
index <HASH>..<HASH> 100644
--- a/squad/core/comparison.py
+++ b/squad/core/comparison.py
@@ -174,7 +174,7 @@ class TestComparison(BaseComparison):
         ).prefetch_related(
             'build',
             'environment',
-        ).only('id')
+        ).only('build', 'environment')
 
         test_runs_ids = {}
         for test_run in test_runs:
core: comparison: fix fetching less data from testrun

This fixes dd<I>a8cb<I>d<I>e<I>b6a9f7a<I>fe0a<I>, which attempted
to prevent unnecessary data from loading. I assumed that Django would
still prefetch "build" and "environment", but it didn't. This caused
collateral unnecessary load of same build and environment.

This explicitly says that only build, environment and id are fetched from
the db