[FLINK-17794][tests] Tear down installed software in reverse order

Tear down installed software in reverse order in Jepsen tests. This
mitigates the issue that sometimes YARN's NodeManager directories cannot
be removed using 'rm -rf' because Flink processes keep running and
generate files after the YARN NodeManager is shut down. rm -r removes
files recursively but if files are created in the background
concurrently, the command can still fail with a non-zero exit code.

This closes apache#12249.

flink-jepsen/src/jepsen/flink/db.clj

@@ -109,7 +109,7 @@
  (teardown! [_ test node]
  (c/su
  (try
- (doseq [db dbs] (db/teardown! db test node))
+ (doseq [db (reverse dbs)] (db/teardown! db test node))
  (finally (fu/stop-all-supervised-services!)))))
  db/LogFiles
  (log-files [_ test node]