temporarily disable output testing for Coq 8.11

Makefile.coq.local

@@ -8,7 +8,8 @@ test: $(TESTFILES:.v=.vo)
 .PHONY: test
 
 COQ_TEST=$(COQTOP) $(COQDEBUG) -batch -test-mode
-COQ_OLD=$(shell echo "$(COQ_VERSION)" | egrep "^8\.7\b" -q && echo 1)
+# FIXME: temporarily disabled on Coq master to help them land a patch
+COQ_OLD=$(shell echo "$(COQ_VERSION)" | egrep "^8\.(7|11)\b" -q && echo 1)
 COQ_MINOR_VERSION=$(shell echo "$(COQ_VERSION)" | egrep '^[0-9]+\.[0-9]+\b' -o)
 
 tests/.coqdeps.d: $(TESTFILES)