Summary:
https://github.com/yugabyte/yugabyte-db/issues/24384 identifies an issue where a `name_col LIKE text_val` condition cannot be pushed down to DocDB because, with the upgrade to pg15, the condition is broken into `name_col > text_val_prefix AND name_col < text_val_prefix2`. Previously, on YB pg11, the condition would have been broken into `name_col > text_val_prefix::name AND ...`, which could be pushed down to DocDB. This does not result in a correctness issue, because the rows get rechecked later.

This change causes the bitmap scan system tests to fail.

To fix this test in the meantime, use the new row counts. Also, update the results to account for the new roles introduced by pg15. When we fix #24384, this test will need to be updated again.

Jira: DB-13188

Test Plan:
```
./yb_build.sh release --java-test 'org.yb.pgsql.TestPgRegressYbBitmapScans'
```

```
grep "Bitmap" pg15_tests/passing_tests.tsv | pg15_tests/run_tests.sh
```

Reviewers: amartsinchyk, tnayak

Reviewed By: amartsinchyk

Subscribers: yql

Differential Revision: https://phorge.dev.yugabyte.com/D38929