Merge pull request #718 from creichert/master

Set `system-filepath` flag to true for Keter.

build-constraints.yaml

@@ -10,8 +10,7 @@ packages:
         - conduit-combinators
         - conduit-extra
         - hebrew-time
-        # https://github.com/fpco/stackage/issues/717
-        #- keter
+        - keter
         - markdown
         - mime-mail
         - mime-mail-ses
@@ -1293,6 +1292,9 @@ package-flags:
     NineP:
         bytestring-in-base: false
 
+    keter:
+        system-filepath: true
+
 # Used for packages that cannot be built on Linux
 skipped-builds:
     - hfsevents