Integrate pg_stat_monitor with test framework

Goal:

Create a list of queries that will generate typical values for all fields (dimensions, metrics, labels, etc.) of pg_stat_monitor.

DOD: 

We will have a tool (script) to create a load on PostgreSQL DB with a new pg_stat_monitor to populate all fields and receive a report to validate if we collect expected metrics.

docker-compose with PostreSQL (pg_stat_monitor) and sysbench-tcc script to create load with needed metrics. 

LINKS: 

https://github.com/percona/pg_stat_monitor/blob/master/docs/USER_GUIDE.md

https://confluence.percona.com/pages/viewpage.action?spaceKey=PMM&title=QAN+PostgreSQL+pg_stat_monitor+data+mapping

Queries to generate metrics: https://github.com/percona/pg_stat_monitor/tree/master/regression/sql

 How to test (no fb needed, only docker compose file attached here, use latest PMM): 
1. Run PMM server
2. Unzip attached docker compose and testqueries folder and run in extracted folder:

docker-compose -f docker-compose-pg-load.yml up postgres-load

3. Add postgres to PMM monitoring
4. Check metrics here
5. Connect to postgres and check new metrics are filled by query:

SELECT * FROM pg_stat_monitor;