Add hjsonpointer and hjsonschema.

build-constraints.yaml

@@ -2197,6 +2197,10 @@ packages:
         - gi-pango
         - haskell-gi
 
+    "Ian Grant Jeffries <ian@housejeffries.com> @seagreen":
+        - hjsonpointer
+        - hjsonschema
+
     # If you stop maintaining a package you can move it here.
     # It will then be disabled if it starts causing problems.
     # See https://github.com/fpco/stackage/issues/1056