Merge branch 'js/test-lib-windows-emulated-yes' into maint

The emulated "yes" command used in our test scripts has been
tweaked not to spend too much time generating unnecessary output
that is not used, to help those who test on Windows where it would
not stop until it fills the pipe buffer due to lack of SIGPIPE.

* js/test-lib-windows-emulated-yes:
  test-lib: limit the output of the yes utility

Author: gitster

t/test-lib.sh

@@ -907,9 +907,11 @@ yes () {
 		y="$*"
 	fi
 
-	while echo "$y"
+	i=0
+	while test $i -lt 99
 	do
-		:
+		echo "$y"
+		i=$(($i+1))
 	done
 }