Upgrade EOL docker images to Ubuntu 18.04

library/stdarch/ci/docker/aarch64-unknown-linux-gnu/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 RUN apt-get update && apt-get install -y --no-install-recommends \
   gcc \
   ca-certificates \

library/stdarch/ci/docker/arm-unknown-linux-gnueabihf/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 RUN apt-get update && apt-get install -y --no-install-recommends \
   gcc \
   ca-certificates \

library/stdarch/ci/docker/armv7-unknown-linux-gnueabihf/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 RUN apt-get update && apt-get install -y --no-install-recommends \
   gcc \
   ca-certificates \

library/stdarch/ci/docker/i586-unknown-linux-gnu/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 RUN apt-get update && apt-get install -y --no-install-recommends \
   gcc-multilib \
   libc6-dev \

library/stdarch/ci/docker/i686-unknown-linux-gnu/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 RUN apt-get update && apt-get install -y --no-install-recommends \
   gcc-multilib \
   libc6-dev \

library/stdarch/ci/docker/mips-unknown-linux-gnu/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
         gcc libc6-dev qemu-user ca-certificates \

library/stdarch/ci/docker/mips64-unknown-linux-gnuabi64/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
         gcc libc6-dev qemu-user ca-certificates \

library/stdarch/ci/docker/mips64el-unknown-linux-gnuabi64/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
         gcc libc6-dev qemu-user ca-certificates \

library/stdarch/ci/docker/powerpc-unknown-linux-gnu/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
         gcc libc6-dev qemu-user ca-certificates \

library/stdarch/ci/docker/powerpc64-unknown-linux-gnu/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
     gcc \

library/stdarch/ci/docker/powerpc64le-unknown-linux-gnu/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
         gcc libc6-dev qemu-user ca-certificates \

library/stdarch/ci/docker/s390x-unknown-linux-gnu/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
         curl ca-certificates \

library/stdarch/ci/docker/x86_64-unknown-linux-gnu/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:17.10
+FROM ubuntu:18.04
 RUN apt-get update && apt-get install -y --no-install-recommends \
   gcc \
   libc6-dev \