Fix broken quotes in systemd unit file
The quoting for the ExecStart entry is broken as quotes must wrap an
entire argument, and arguments are separated by spaces. It turns out
that any quoting is unnecessary here, systemd will handle it correctly
either way.
@@ -15,7 +15,7 @@ WorkingDirectory=/usr/share/elasticsearch
User=elasticsearch
Group=elasticsearch
-ExecStart=/usr/share/elasticsearch/bin/elasticsearch -p "${PID_DIR}"/elasticsearch.pid --quiet
+ExecStart=/usr/share/elasticsearch/bin/elasticsearch -p ${PID_DIR}/elasticsearch.pid --quiet
# StandardOutput is configured to redirect to journalctl since
# some error messages may be logged in standard output before
