patch 9.0.0560: elapsed time since testing started is not visible

Problem:    Elapsed time since testing started is not visible.
Solution:   Show the elapsed time while running tests.
diff --git a/src/testdir/Makefile b/src/testdir/Makefile
index 54a9989..b69d935 100644
--- a/src/testdir/Makefile
+++ b/src/testdir/Makefile
@@ -12,7 +12,7 @@
 # Comment out this line to see the verbose output of tests.
 #
 # Catches SwapExists to avoid hanging at the ATTENTION prompt.
-REDIR_TEST_TO_NULL = --cmd 'au SwapExists * let v:swapchoice = "e"' | LC_ALL=C LANG=C LANGUAGE=C awk '/Executing Test_/{match($$0, "(took .*; now )?Executing Test_[^\\)]*\\)"); print substr($$0, RSTART, RLENGTH) "\r"; fflush()}'
+REDIR_TEST_TO_NULL = --cmd 'au SwapExists * let v:swapchoice = "e"' | LC_ALL=C LANG=C LANGUAGE=C awk '/Executing Test_/{match($$0, "([0-9][0-9]:[0-9][0-9] *)?Executing Test_[^\\)]*\\)"); print substr($$0, RSTART, RLENGTH) "\r"; fflush()}'
 
 # Uncomment this line to use valgrind for memory leaks and extra warnings.
 #   The output goes into a file "valgrind.testN"
@@ -49,6 +49,7 @@
 		else echo No failures reported > test_result.log; \
 		fi"
 	$(VIMPROG) -u NONE $(NO_INITS) -S summarize.vim messages $(REDIR_TEST_TO_NULL)
+	@rm -f starttime
 	@echo
 	@echo 'Test results:'
 	@cat test_result.log
@@ -63,7 +64,7 @@
 # Execute an individual new style test, e.g.:
 # 	make test_largefile
 $(NEW_TESTS):
-	rm -f $@.res test.log messages
+	rm -f $@.res $(CLEANUP_FILES)
 	@MAKEFLAGS=--no-print-directory $(MAKE) -f Makefile $@.res VIMPROG=$(VIMPROG) XXDPROG=$(XXDPROG) SCRIPTSOURCE=$(SCRIPTSOURCE)
 	@cat messages
 	@if test -f test.log; then \
@@ -72,9 +73,10 @@
 
 # Run only tests specific for Vim9 script
 test_vim9:
-	rm -f test_vim9_*.res test.log messages
+	rm -f test_vim9_*.res $(CLEANUP_FILES)
 	@MAKEFLAGS=--no-print-directory $(MAKE) -f Makefile $(TEST_VIM9_RES) VIMPROG=$(VIMPROG) XXDPROG=$(XXDPROG) SCRIPTSOURCE=$(SCRIPTSOURCE)
 	@cat messages
+	@rm -f starttime
 	@MAKEFLAGS=--no-print-directory $(MAKE) -f Makefile report VIMPROG=$(VIMPROG) XXDPROG=$(XXDPROG) SCRIPTSOURCE=$(SCRIPTSOURCE)
 	@if test -f test.log; then \
 		exit 1; \
@@ -88,7 +90,7 @@
 # that may result from working on the tests, not only from running them.
 clean:
 	-rm -rf *.out *.failed *.res *.rej *.orig XfakeHOME Xdir1 Xfind
-	-rm -f opt_test.vim test.log test_result.log messages
+	-rm -f opt_test.vim test_result.log $(CLEANUP_FILES)
 	-rm -rf $(RM_ON_RUN) $(RM_ON_START)
 	-rm -f valgrind.*
 	-rm -f asan.*
@@ -99,7 +101,7 @@
 	rm -f $(SCRIPTS_BENCH)
 
 nolog:
-	-rm -f test.log test_result.log messages
+	-rm -f test_result.log $(CLEANUP_FILES)
 
 
 # Tiny tests.  Works even without the +eval feature.