[#26663] YSQL: Remove ysql_major_upgrade_pgregress-test

Summary:
Delete ysql_major_upgrade_pgregress-test.cc.
Jira: DB-16041

Test Plan: Jenkins: compile only

Reviewers: telgersma

Reviewed By: telgersma

Subscribers: yql

Differential Revision: https://phorge.dev.yugabyte.com/D42996

Author: fizaaluthra

src/yb/integration-tests/CMakeLists.txt

@@ -283,7 +283,6 @@ ADD_YB_TEST(upgrade-tests/ysql_major_upgrade_conn_mgr-test)
 ADD_YB_TEST(upgrade-tests/ysql_major_upgrade_ddl_blocking-test)
 ADD_YB_TEST(upgrade-tests/ysql_major_upgrade_expression_pushdown-test)
 ADD_YB_TEST(upgrade-tests/ysql_major_upgrade_matview-test)
-ADD_YB_TEST(upgrade-tests/ysql_major_upgrade_pgregress-test)
 ADD_YB_TEST(upgrade-tests/ysql_major_upgrade_rpcs-test)
 ADD_YB_TEST(upgrade-tests/ysql_major_upgrade-test)