vagrant: darwin64 box: install openssl after xxhash

otherwise a openssl build error might manifest in complaints about xxhash not being installed.

Vagrantfile

@@ -111,7 +111,7 @@ def packages_darwin
     sudo softwareupdate --install --all
     which brew || CI=1 /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"
     brew update > /dev/null
-    brew install pkg-config readline openssl@1.1 xxhash zstd lz4 xz
+    brew install pkg-config readline xxhash zstd lz4 xz openssl@1.1
     brew install --cask macfuse
     # brew upgrade  # upgrade everything (takes rather long)
     echo 'export PKG_CONFIG_PATH=/usr/local/opt/openssl@1.1/lib/pkgconfig' >> ~vagrant/.bash_profile