drpc: run existing SQL logictest tests with DRPC enabled at random

Currently, SQL logictest tests run exclusively with gRPC. Add support for running these tests with DRPC as well by introducing a package level setting that randomly selects between gRPC and DRPC, similar to the mechanism used for secondary tenants.

When we simply enable DRPC in the tests in the `pkg/sql/logictest`, the following tests fail (tested in all tenant modes):

```
FAIL pkg/sql/logictest/tests/5node-disk (tenant=external)
FAIL pkg/sql/logictest/tests/5node-disk (tenant=shared)
FAIL pkg/sql/logictest/tests/fakedist (tenant=false)
FAIL pkg/sql/logictest/tests/fakedist (tenant=external)
FAIL pkg/sql/logictest/tests/fakedist (tenant=shared)
FAIL pkg/sql/logictest/tests/fakedist-disk (tenant=false)
FAIL pkg/sql/logictest/tests/fakedist-disk (tenant=external)
FAIL pkg/sql/logictest/tests/fakedist-disk (tenant=shared)
FAIL pkg/sql/logictest/tests/fakedist-vec-off (tenant=false)
FAIL pkg/sql/logictest/tests/fakedist-vec-off (tenant=external)
FAIL pkg/sql/logictest/tests/fakedist-vec-off (tenant=shared)
FAIL pkg/sql/logictest/tests/local (tenant=false)
FAIL pkg/sql/logictest/tests/local (tenant=external)
FAIL pkg/sql/logictest/tests/local (tenant=shared)
FAIL pkg/sql/logictest/tests/local-legacy-schema-changer (tenant=false)
FAIL pkg/sql/logictest/tests/local-legacy-schema-changer (tenant=external)
FAIL pkg/sql/logictest/tests/local-legacy-schema-changer (tenant=shared)
FAIL pkg/sql/logictest/tests/local-mixed-25.2 (tenant=false)
FAIL pkg/sql/logictest/tests/local-mixed-25.2 (tenant=external)
FAIL pkg/sql/logictest/tests/local-mixed-25.2 (tenant=shared)
FAIL pkg/sql/logictest/tests/local-mixed-25.3 (tenant=false)
FAIL pkg/sql/logictest/tests/local-mixed-25.3 (tenant=external)
FAIL pkg/sql/logictest/tests/local-mixed-25.3 (tenant=shared)
FAIL pkg/sql/logictest/tests/local-mixed-25.4 (tenant=false)
FAIL pkg/sql/logictest/tests/local-mixed-25.4 (tenant=external)
FAIL pkg/sql/logictest/tests/local-mixed-25.4 (tenant=shared)
FAIL pkg/sql/logictest/tests/local-prepared (tenant=external)
FAIL pkg/sql/logictest/tests/local-prepared (tenant=shared)
FAIL pkg/sql/logictest/tests/local-vec-off (tenant=false)
FAIL pkg/sql/logictest/tests/local-vec-off (tenant=external)
FAIL pkg/sql/logictest/tests/local-vec-off (tenant=shared)
```

Epic: [CRDB-48935](https://cockroachlabs.atlassian.net/browse/CRDB-48935)

Jira issue: CRDB-56410