overiding policy.xml on docker

I was following the link https://help.heroku.com/RFDJQSG3/how-can-i-override-imagemagick-settings-in-a-policy-xml-file to override the default policy.xml of mini magic, but it is not happning.

Step taken by me.

1. I created an .magic/policy.xml in my root_path
2. In my environment i set the "MAGICK_CONFIGURE_PATH" => "/app/.magick/:/etc/ImageMagick-6/",

but still when i try identify -list policy

i still have result

Path: /etc/ImageMagick-6/policy.xml
  Policy: undefined
    rights: None 
  Policy: Coder
    rights: None 
    pattern: EPHEMERAL
  Policy: Coder
    rights: None 
    pattern: URL
  Policy: Coder
    rights: None 
    pattern: HTTPS
  Policy: Coder
    rights: None 
    pattern: MVG
  Policy: Coder
    rights: None 
    pattern: MSL
  Policy: Coder
    rights: None 
    pattern: TEXT
  Policy: Coder
    rights: None 
    pattern: SHOW
  Policy: Coder
    rights: None 
    pattern: WIN
  Policy: Coder
    rights: None 
    pattern: PLT
  Policy: Path
    rights: None 
    pattern: @*

Path: [built-in]
  Policy: Undefined
    rights: None 

It is not getting overrided.