[fix](regression-test) fix flaky case test_partial_update_compaction_with_higher_version (#41717)

diff --git a/regression-test/suites/fault_injection_p0/partial_update/test_partial_update_compaction_with_higher_version.groovy b/regression-test/suites/fault_injection_p0/partial_update/test_partial_update_compaction_with_higher_version.groovy
index 7af5366..b5ae149 100644
--- a/regression-test/suites/fault_injection_p0/partial_update/test_partial_update_compaction_with_higher_version.groovy
+++ b/regression-test/suites/fault_injection_p0/partial_update/test_partial_update_compaction_with_higher_version.groovy
@@ -194,7 +194,7 @@
 
         // let the second partial update load publish
         disable_block_in_publish()
-        t1.join()
+        t2.join()
         Thread.sleep(300)
 
         order_qt_sql "select * from ${table1};"