Makefile: Don't depend on $(SPEC)

The spec file is always present.

Makefile

@@ -153,11 +153,11 @@ update-spec:
 	curl 'https://raw.githubusercontent.com/jgm/CommonMark/master/spec.txt'\
  > $(SPEC)
 
-test: $(SPEC) cmake_build
+test: cmake_build
 	ctest --test-dir $(BUILDDIR) --output-on-failure || (cat $(BUILDDIR)/Testing/Temporary/LastTest.log && exit 1)
 
-$(ALLTESTS): $(SPEC)
-	python3 test/spec_tests.py --spec $< --dump-tests | python3 -c 'import json; import sys; tests = json.loads(sys.stdin.read()); print("\n".join([test["markdown"] for test in tests]))' > $@
+$(ALLTESTS):
+	python3 test/spec_tests.py --spec $(SPEC) --dump-tests | python3 -c 'import json; import sys; tests = json.loads(sys.stdin.read()); print("\n".join([test["markdown"] for test in tests]))' > $@
 
 leakcheck: $(ALLTESTS)
 	for format in html man xml latex commonmark; do \

Makefile.nmake

@@ -2,7 +2,6 @@ SRCDIR=src
 DATADIR=data
 BUILDDIR=build
 INSTALLDIR=windows
-SPEC=test/spec.txt
 PROG=$(BUILDDIR)\src\cmark.exe
 GENERATOR=NMake Makefiles
 
@@ -21,7 +20,7 @@ install: all
 clean:
 	-rmdir /s /q $(BUILDDIR) $(MINGW_INSTALLDIR) 2> nul
 
-test: $(SPEC) all
+test: all
 	ctest --test-dir $(BUILDDIR) --output-on-failure
 
 distclean: clean