Merge branch 'master' of jeffery/elxr into master

linux/centos/elxr/setup.sh

 sudo systemctl restart chronyd
 
 # Display NTP synchronization status
-chronyc tracking
+chronyc tracking
+
+# If pm2 command not found
+# Step 1
+# npm config get prefix
+# Step 2
+# Might give a path like /usr/local/lib/node-v20.8.0-linux-x64
+# Append path with /bin
+# export PATH=$PATH:/usr/local/lib/node-v20.8.0-linux-x64/bin 
+# Step 3
+# Check pm2
+# pm2