fix(stats-detectors): Increase regression fingerprint length (#61733)

The fingerprint length can actually be longer.

migrations_lockfile.txt

@@ -9,5 +9,5 @@ feedback: 0003_feedback_add_env
 hybridcloud: 0009_make_user_id_optional_for_slug_reservation_replica
 nodestore: 0002_nodestore_no_dictfield
 replays: 0003_add_size_to_recording_segment
-sentry: 0622_add_has_custom_metrics_flag
+sentry: 0623_increase_regression_fingerprint_length
 social_auth: 0002_default_auto_field

src/sentry/migrations/0623_increase_regression_fingerprint_length.py

@@ -0,0 +1,31 @@
+# Generated by Django 3.2.23 on 2023-12-14 16:54
+
+from django.db import migrations, models
+
+from sentry.new_migrations.migrations import CheckedMigration
+
+
+class Migration(CheckedMigration):
+    # This flag is used to mark that a migration shouldn't be automatically run in production. For
+    # the most part, this should only be used for operations where it's safe to run the migration
+    # after your code has deployed. So this should not be used for most operations that alter the
+    # schema of a table.
+    # Here are some things that make sense to mark as dangerous:
+    # - Large data migrations. Typically we want these to be run manually by ops so that they can
+    #   be monitored and not block the deploy for a long period of time while they run.
+    # - Adding indexes to large tables. Since this can take a long time, we'd generally prefer to
+    #   have ops run this and not block the deploy. Note that while adding an index is a schema
+    #   change, it's completely safe to run the operation after the code has deployed.
+    is_dangerous = False
+
+    dependencies = [
+        ("sentry", "0622_add_has_custom_metrics_flag"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="regressiongroup",
+            name="fingerprint",
+            field=models.CharField(max_length=64),
+        ),
+    ]

src/sentry/models/statistical_detectors.py

@@ -63,8 +63,9 @@ class RegressionGroup(Model):
 
     # The fingerprint sent to the issue platform which
     # accepts a list of strings. This corresponds to the
-    # first string which is a 8-16 char hex value.
-    fingerprint = models.CharField(max_length=32)
+    # first string which is a 8 char hex for functions
+    # and a 40 char hex for transactions
+    fingerprint = models.CharField(max_length=64)
 
     # The value measured from before the regression.
     baseline = models.FloatField()