### ImageMagick version

`HEAD`

### Operating system

Linux

### Operating system, version and so on

Ubuntu 22.04

### Description

`Magick.SetSecurityPolicy("invalid");` returns `true` without doing anything

### Steps to Reproduce

`Magick.SetSecurityPolicy("invalid");`

### Images

_No response_
`Magick::SetSecurityPolicy` / `MagickCore::SetMagickSecurityPolicy` return true on completely invalid XML
This is a GitHub Issue
repo:ImageMagick
owner:ImageMagick
Title : `Magick::SetSecurityPolicy` / `MagickCore::SetMagickSecurityPolicy` return true on completely invalid XML
Issue date:

--- start body ---
### ImageMagick version

`HEAD`

### Operating system

Linux

### Operating system, version and so on

Ubuntu 22.04

### Description

`Magick.SetSecurityPolicy("invalid");` returns `true` without doing anything

### Steps to Reproduce

`Magick.SetSecurityPolicy("invalid");`

### Images

_No response_
--- end body ---
