Summary:
On adding the support to run c++ test with ysql connection manager ([[ https://phorge.dev.yugabyte.com/D29027 | D29027 ]]) has lead to many **asan** and **tsan** build tests failure. This diff fixes in the following ways:

  - **Asan Fix**: Tests were failing due to memory leak caused by `strdup` function used in the postmaster.c. This was occurring with auth-backend where backend connection is explicitly closed just after authentication and memory is not cleaned up.  Replacing it with `pstrdup` fixes the leak.

  - **Tsan Fix**: Tests were failing due to data race conditions at various places in the odyssey code. Required locks has been added in this diff to avoid race conditions.
Jira: DB-14952

Test Plan: Jenkins: enable connection manager, all tests

Reviewers: rbarigidad, vpatibandla, skumar, devansh.saxena

Reviewed By: devansh.saxena

Subscribers: yql

Differential Revision: https://phorge.dev.yugabyte.com/D41366