Stacktrace recovery doesn't filter out exceptions with modified message

[qwwdfsad]

This is a rarely-reproducing leftover of #1631

Steps to reproduce:

class WrongMessageException(token: String) : RuntimeException("Token $token")

@Test
fun testWrongMessageExceptionInChannel() = runTest {
    // Separate code path
    val result = produce<Unit>(SupervisorJob() + Dispatchers.Unconfined) {
        throw WrongMessageException("OK")
    }
    val ex = runCatching {
        for (unit in result) {
            // Iterator has a special code path
        }
    }.exceptionOrNull() ?: error("Expected to fail")
    assertTrue(ex is WrongMessageException)
    assertEquals("Token OK", ex.message)
}