Disable cross-platform build for arm32v7

https://github.com/jellyfin/jellyfin/issues/665

Dockerfile.arm

@@ -1,14 +1,7 @@
 ARG DOTNET_VERSION=2.2
 
 
-FROM multiarch/qemu-user-static:x86_64-arm as qemu
-FROM alpine as qemu_extract
-COPY --from=qemu /usr/bin qemu_user_static.tgz
-RUN tar -xzvf qemu_user_static.tgz
-
-
 FROM microsoft/dotnet:${DOTNET_VERSION}-sdk-stretch-arm32v7 as builder
-COPY --from=qemu_extract qemu-* /usr/bin
 WORKDIR /repo
 COPY . .
 #TODO Remove or update the sed line when we update dotnet version.
@@ -22,7 +15,6 @@ RUN export DOTNET_CLI_TELEMETRY_OPTOUT=1 \
 
 
 FROM microsoft/dotnet:${DOTNET_VERSION}-runtime-stretch-slim-arm32v7
-COPY --from=qemu_extract qemu-* /usr/bin
 COPY --from=builder /jellyfin /jellyfin
 EXPOSE 8096
 RUN apt-get update \