FIR: add test for KT-51357

compiler/testData/diagnostics/testsWithStdLib/greater.kt

@@ -0,0 +1,12 @@
+class Expression<T>(val x: T)
+
+class GreaterOp(val expr1: Expression<*>, val expr2: Expression<*>)
+
+fun <T : Comparable<T>, S : T?> Expression<in S>.greater(other: T): GreaterOp =
+    GreaterOp(this, Expression(other))
+
+fun foo(countExpr: Expression<Long>) {
+    countExpr.greater(0)
+    countExpr.greater("0")
+    countExpr.greater<String, Nothing>("0")
+}