[test] Add lto test configs to passing_core_test_modes. NFC

[sbc100]

Without this, one cannot do things like ./test/runner lto0.test_foo*.

[juj]

Oh so this is why running somesuite.test_foo* often fails. The suite must be in the list of passing_core_test_modes for the wildcard to work?

[sbc100]

Oh so this is why running somesuite.test_foo* often fails. The suite must be in the list of passing_core_test_modes for the wildcard to work?

Yes... probably we should fix that .. but that seems to be how it works today.