tests: fix num_lit_call_method_test

vlib/v/tests/num_lit_call_method_test.v

@@ -0,0 +1,28 @@
+fn test_int_lit_call_method() {
+    x1 := 1234.str()
+    assert x1 == '1234'
+    x2 := -0xffff.str()
+    assert x2 == '-65535'
+    x3 := 0b1001001.str()
+    assert x3 == '73'
+    x4 := 0o653262.str()
+    assert x4 == '218802'
+    x5 := 0.str()
+    assert x5 == '0'
+}
+
+fn test_float_lit_call_method() {
+    x1 := -123.66.str()
+    assert x1 == '-1.2366e+02'
+    x2 := 12.5e-2.str()
+    assert x2 == '1.25e-01'
+    x3 := .789.str()
+    assert x3 == '7.89e-01'
+    x4 := .003e2.str()
+    assert x4 == '3.e-01'
+    x5 := 2.e-3.str() 
+    assert x5 == '2.e-03'
+    x6 := 5.0.str()
+    assert x6 == '5.e+00'
+    // x7 := 5..str()    Syntax `5.` is allowed, but do not call method on it (`5..str()` is parsed as a range). Use `5.0.str()` instead.
+}