Fix KT-51478

The issue was that, when various context elements were available
to fulfill a need for an extension receiver, but none of them were
applicable to it, the compiler behaved the same way as if there
was no extension receiver at all.

https://youtrack.jetbrains.com/issue/KT-51478/Inapplicable-receiver-diagnostic-expected-when-there-are-two-context-receiver-candidates

compiler/testData/diagnostics/tests/extensions/contextReceivers/twoReceiverCandidatesError.txt

@@ -0,0 +1,5 @@
+package
+
+context(kotlin.Int, kotlin.Double) public fun bar(): kotlin.Unit
+public fun main(): kotlin.Unit
+public fun kotlin.String.foo(): kotlin.Unit