Update LIB_HEIF_VERSION to 1.21.2

Author: mihxil

Dockerfile

@@ -8,7 +8,7 @@ LABEL "org.opencontainers.image.description"="An ubuntu image with imagemagick 7
 # Borrowed from: https://github.com/dooman87/imagemagick-docker
 
 ARG IM_VERSION=7.1.2-12
-ARG LIB_HEIF_VERSION=1.19.8
+ARG LIB_HEIF_VERSION=1.21.2
 ARG LIB_AOM_VERSION=3.12.1
 ARG LIB_WEBP_VERSION=1.6.0
 ARG LIBJXL_VERSION=0.11.1