### Godot version

4.1.1

### System information

linux

### Issue description

The `"%+f"` format adds a `+` sign in front of positive numbers. If you try to format `-0.0`, it breaks and displays both a `+` and a `-`.

### Steps to reproduce

```gdscript
@tool
extends EditorScript

func _run() -> void:
    print("%+f" % -0.0)
```

### Minimal reproduction project

see above
Error err = s.parse_utf8((const char *)u8str);
	CHECK(err == OK);
	CHECK(s == u32str);
	CharString cs = (const char *)u8str;
	CHECK(String::utf8(cs) == s);
}
TEST_CASE("[String] UTF16 with BOM") {
	
	static const char32_t u32str[] = { 0x0020, 0x0045, 0x304A, 0x360F, 0x3088, 0x3046, 0x1F3A4, 0 };
	static const char16_t u16str[] = { 0xFEFF, 0x0020, 0x0045, 0x304A, 0x360F, 0x3088, 0x3046, 0xD83C, 0xDFA4, 0 };
	static const char16_t u16str_swap[] = { 0xFFFE, 0x2000, 0x4500, 0x4A30, 0x0F36, 0x8830, 0x4630, 0x3CD8, 0xA4DF, 0 };
	String s;
	Error err = s.parse_utf16(u16str);
	CHECK(err == OK);
	CHECK(s == u32str);
	err = s.parse_utf16(u16str_swap);
	CHECK(err == OK);
	CHECK(s == u32str);
	Char16String cs = u16str;
	CHECK(String::utf16(cs) == s);
	cs = u16str_swap;
	CHECK(String::utf16(cs) == s);
}
TEST_CASE("[String] UTF8 with CR") {
	const String base = U"Hello darkness\r\nMy old friend\nI've come to talk\rWith you again";
	String keep_cr;
	Error err = keep_cr.parse_utf8(base.utf8().get_data());
	CHECK(err == OK);
	CHECK(keep_cr == base);
	String no_cr;