Allow building with th-abstraction-0.7.*

invariant.cabal

@@ -57,7 +57,7 @@ library
                      , stm                  >= 2.2    && < 3
                      , tagged               >= 0.7.3  && < 1
                      , template-haskell     >= 2.4    && < 2.22
-                     , th-abstraction       >= 0.4    && < 0.7
+                     , th-abstraction       >= 0.4    && < 0.8
                      , transformers         >= 0.2    && < 0.7
                      , transformers-compat  >= 0.3    && < 1
                      , unordered-containers >= 0.2.4  && < 0.3