fix(migrations): Actually fix BoundedPositiveBigIntegerField (#83431)

Third time's the charm!

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Author: wedamija

src/sentry/db/models/fields/bounded.py

@@ -66,7 +66,7 @@ class BoundedPositiveBigIntegerField(models.PositiveBigIntegerField):
         MAX_VALUE = 9223372036854775807
 
         def get_internal_type(self) -> str:
-            return "BigIntegerField"
+            return "PositiveBigIntegerField"
 
         def get_prep_value(self, value: int) -> int:
             if value: