FIR: rename HIDDEN to INVISIBLE_REFERENCE

Some of them should be INVISIBLE_MEMBER though

compiler/testData/diagnostics/tests/resolve/invoke/errors/invisibleInvoke.fir.kt

@@ -5,6 +5,6 @@ class My {
 }
 
 fun My.foo(i: Int) {
-    <!HIDDEN!>i<!>("")
-    <!HIDDEN!>1<!>("")
+    <!INVISIBLE_REFERENCE!>i<!>("")
+    <!INVISIBLE_REFERENCE!>1<!>("")
 }

compiler/testData/diagnostics/tests/resolve/noCandidates/resolvedToClassifier.fir.kt

@@ -9,7 +9,7 @@ fun test() {
     val interface_as_fun = <!UNRESOLVED_REFERENCE!>A<!>()
     val interface_as_val = A
 
-    val object_as_fun = <!HIDDEN!>B<!>()
+    val object_as_fun = <!INVISIBLE_REFERENCE!>B<!>()
     val class_as_val = C
 }
 

compiler/testData/diagnostics/tests/resolve/noCandidates/resolvedToClassifierWithReceiver.fir.kt

@@ -11,7 +11,7 @@ fun testX() {
     val interface_as_fun = X.<!UNRESOLVED_REFERENCE!>A<!>()
     val interface_as_val = X.A
 
-    val object_as_fun = X.<!HIDDEN!>B<!>()
+    val object_as_fun = X.<!INVISIBLE_REFERENCE!>B<!>()
     val class_as_val = X.C
 }
 
@@ -26,7 +26,7 @@ fun testY() {
     val interface_as_fun = Y.<!UNRESOLVED_REFERENCE!>A<!>()
     val interface_as_val = Y.A
 
-    val object_as_fun = Y.<!HIDDEN!>B<!>()
+    val object_as_fun = Y.<!INVISIBLE_REFERENCE!>B<!>()
     val class_as_val = Y.C
 }