revert clock to 0.5.1 (last version with fromInteger instance, #1305)

move clock from skipped-tests to expected-test-failures (#1045)

build-constraints.yaml

@@ -219,7 +219,8 @@ packages:
         - uuid
 
     "Philipp Middendorf <pmidden@secure.mailbox.org>":
-        - clock
+        # https://github.com/fpco/stackage/issues/1305
+        - clock < 0.5.2
 
     "Stefan Wehr <wehr@factisresearch.com>":
         - HTF
@@ -2251,7 +2252,6 @@ skipped-tests:
     # Misc from GHC 7.10.3 upgrade
     # https://github.com/fpco/stackage/issues/1045
     #- argon
-    - clock
 
     # HUnit < 1.3
     - GLFW-b
@@ -2579,6 +2579,9 @@ expected-test-failures:
 
     # https://github.com/elaye/turtle-options/issues/3
     - turtle-options
+
+    # https://github.com/fpco/stackage/issues/1045 (moved here from skipped-tests)
+    - clock
 # end of expected-test-failures