Once a “Liquibase” SQL is running it will behave like any other client connection to the database. The DBMS will handle transaction control how it normally would. Speaking for Oracle, the ALTER TABLE transaction would get rolled-back. The only thing specific to Liquibase is that the Liquibase “lock” will be left “on” in the databasechangeloglock table since the Liquibase process was killed, and you will need to run the release-locks command to remove it.
I’d recommend putting a process in place to prevent your pod from stopping if Liquibase is running. See this topic for an example that I have implemented: