Shared file management of multiple websites?

I"d like to ask a question
suppose there are three websites on different servers
, but all three sites have common files, which may include js, css, and some php function
. How can I manage shared files at this time?
if the shared file is updated, will it be deployed to three servers?
what is the more convenient way to do this?
or what is the right thing to do?
Thank you
Happy New year!

Jun.08,2022
The

code can be handled automatically with git HOOK.
Resource files can be placed on only one of the servers.

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b34f73-2bf3e.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b34f73-2bf3e.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?