JVM IR: Avoid direct invokes in callable reference tests

Due to the direct invoke optimization, most callable reference tests
were not generating callable references/lambdas.

compiler/testData/codegen/box/jvm8/defaults/accessor.kt

@@ -24,7 +24,7 @@ interface Test {
         return {
             foo = "O"
             foo + bar()
-        } ()
+        }.let { it() }
     }
 }
 

compiler/testData/codegen/box/jvm8/defaults/accessorsFromDefaultImpls.kt

@@ -14,7 +14,7 @@ interface Test {
     }
 
     fun call(): String {
-        return { foo + bar()} ()
+        return { foo + bar() }.let { it() }
     }
 }
 

compiler/testData/codegen/box/jvm8/defaults/allCompatibility/accessor.kt

@@ -21,7 +21,7 @@ interface Test {
         return {
             foo = "O"
             foo + bar()
-        } ()
+        }.let { it() }
     }
 }
 

compiler/testData/codegen/box/jvm8/defaults/callableReference.kt

@@ -12,7 +12,7 @@ interface Test {
         get() = "K"
 
     fun test(): String {
-        return (::foo)() + (::bar)()
+        return (::foo).let { it() } + (::bar).let { it() }
     }
 }
 

compiler/testData/codegen/box/jvm8/defaults/noDefaultImpls/accessor.kt

@@ -21,7 +21,7 @@ interface Test {
         return {
             foo = "O"
             foo + bar()
-        } ()
+        }.let { it() }
     }
 }