Update vprintf_variation5 test expectation for negative zero fix

The GH-12237 fix correctly removes the negative sign when the value
rounds to zero. Update the expected output for -2e-5 formatted with
%04.4f: -0.0000 becomes 0.0000.

Author: lacatoire

ext/standard/tests/strings/vprintf_variation5.phpt

@@ -64,8 +64,8 @@ int(28)
 int(54)
 
 -- Iteration 4 --
-200000.0000 0.0000     -200000.000000 -0.0000
-int(45)
+200000.0000 0.0000     -200000.000000 0.0000
+int(44)
 
 -- Iteration 5 --
 20000.000000 -1999999999999999879418332743206357172224.000000 0.000000 20000000000000000000.000000