CI: Use dot-dot syntax with git-log

.github/workflows/haskell-actions.yml

@@ -39,7 +39,7 @@ jobs:
           fi
           echo $GITHUB_SHA
           git show $GITHUB_SHA
-          for constraint in $(git log "--format=%(trailers:key=New-Versions,valueonly=true)" ${GITHUB_SHA}^1 ${GITHUB_SHA}^2)
+          for constraint in $(git log "--format=%(trailers:key=New-Versions,valueonly=true)" ${GITHUB_SHA}^1..${GITHUB_SHA}^2)
             do echo "constraints: $constraint" >> cabal.project
           done
           cat cabal.project