CI: enable clang tests (#898)

Summary: Pull Request resolved: facebookincubator/zstrong#898

Reviewed By: malanka

Differential Revision: D59065671

fbshipit-source-id: 2a09ae13e1d4c62a7b9a907cca0e911672435ad1

Makefile

@@ -83,7 +83,7 @@ endif
 
 CABAL = $(CABAL_BIN) --jobs --ghc-options='$(EXTRA_GHC_OPTS)' \
             -vnormal+nowrap --project-file=$(PWD)/cabal.project \
-			$(CABAL_CONFIG_FLAGS)
+			$(CABAL_CONFIG_FLAGS) $(GETDEPS_CABAL_FLAGS)
 
 BUILD_DIR = .build
 MODE_DIR = $(BUILD_DIR)/$(MODE)