ci: 7-zip instead of info-zip for windows

I'm guessing this is why 0.3.0 is 21.5MiB while
master is 27.6MiB

ci/azure/windows_install

@@ -3,7 +3,7 @@
 set -x
 set -e
 
-pacman -S --needed --noconfirm wget zip python3-pip
+pacman -S --needed --noconfirm wget p7zip python3-pip
 pip install s3cmd
 wget -nv "https://ziglang.org/deps/llvm%2bclang-7.0.0-win64-msvc-release.tar.xz"
 tar xf llvm+clang-7.0.0-win64-msvc-release.tar.xz

ci/azure/windows_upload

@@ -15,7 +15,7 @@ if [ "${BUILD_REASON}" != "PullRequest" ]; then
   DIRNAME="zig-windows-x86_64-$VERSION"
   TARBALL="$DIRNAME.zip"
   mv release "$DIRNAME"
-  zip -r "$TARBALL" "$DIRNAME"
+  7z a "$TARBALL" "$DIRNAME"
 
   mv "$DOWNLOADSECUREFILE_SECUREFILEPATH" "$HOME/.s3cfg"
   s3cmd put -P "$TARBALL" s3://ziglang.org/builds/