Fix bug with build filter (#10528)

* Fix bug with build filter

This was silently failing, I guess because Build.type is a field. The
filter should instead be filtering against Build.version.type.

* Change build filter field name

readthedocs/builds/filters.py

@@ -43,11 +43,11 @@ class BuildListFilter(FilterSet):
         empty_label=_("Any"),
         method="get_state",
     )
-    type = ChoiceFilter(
+    version__type = ChoiceFilter(
         label=_("Type"),
         choices=TYPE_CHOICES,
         empty_label=_("Any"),
-        method="get_type",
+        method="get_version_type",
     )
 
     def get_state(self, queryset, _, value):
@@ -62,9 +62,9 @@ def get_state(self, queryset, _, value):
             )
         return queryset
 
-    def get_type(self, queryset, _, value):
+    def get_version_type(self, queryset, _, value):
         if value == self.TYPE_NORMAL:
-            queryset = queryset.exclude(type=EXTERNAL)
+            queryset = queryset.exclude(version__type=EXTERNAL)
         elif value == self.TYPE_EXTERNAL:
-            queryset = queryset.filter(type=EXTERNAL)
+            queryset = queryset.filter(version__type=EXTERNAL)
         return queryset