Summary:
PgPartmanTest performs hundreds of table modification tasks, it takes significant amount of time especially in ASAN mode.
So those tests does not fit into default timeout:

PgPartmanTest.TestIdTimeSubpartNative
PgPartmanTest.TestIdTimeSubpartCustomStartNative

Increased timeout to 1200 seconds in ASAN mode
Jira: DB-14279

Test Plan:
./yb_build.sh asan --gtest_filter PgPartmanTest.TestIdTimeSubpartNative
./yb_build.sh asan --gtest_filter PgPartmanTest.TestIdTimeSubpartCustomStartNative

Reviewers: devansh.saxena, skumar

Reviewed By: devansh.saxena

Subscribers: yql, ybase

Tags: #jenkins-ready

Differential Revision: https://phorge.dev.yugabyte.com/D40356