Push $ARCH into Docker image

Author: Xyene

.travis.yml

@@ -18,7 +18,7 @@ install:
 script:
   - export PYTHON_DIR="python$(echo "$PYTHON_VERSION" | cut -d. -f 1-2)"
   - export PYTHON_URL="https://www.python.org/ftp/python/$(perl -e 'shift=~/([\d.]+)/;print$1' "$PYTHON_VERSION")/Python-$PYTHON_VERSION.tar.xz"
-  - docker run -e PYTHON_DIR="$PYTHON_DIR" -e PYTHON_URL="$PYTHON_URL" -v "$(pwd):/code" dmoj/runtimes-tier1:"${ARCH}"-latest
+  - docker run -e ARCH="$ARCH" PYTHON_DIR="$PYTHON_DIR" -e PYTHON_URL="$PYTHON_URL" -v "$(pwd):/code" dmoj/runtimes-tier1:"${ARCH}"-latest
 deploy:
   provider: releases
   api_key: