Fix "Remove @ from annotation argument" (make consistent PSI)

Three relevant quick-fix tests should be fixed after it

idea/testData/quickfix/removeAtFromAnnotationArgument/namedParam.kt

@@ -1,5 +1,4 @@
 // "Remove @ from annotation argument" "true"
-// ERROR: An annotation argument must be a compile-time constant
 
 annotation class Y()
 annotation class X(val value: Y, val y: Y)

idea/testData/quickfix/removeAtFromAnnotationArgument/namedParam.kt.after

@@ -1,5 +1,4 @@
 // "Remove @ from annotation argument" "true"
-// ERROR: An annotation argument must be a compile-time constant
 
 annotation class Y()
 annotation class X(val value: Y, val y: Y)

idea/testData/quickfix/removeAtFromAnnotationArgument/simple.kt

@@ -1,5 +1,4 @@
 // "Remove @ from annotation argument" "true"
-// ERROR: An annotation argument must be a compile-time constant
 
 annotation class Y()
 annotation class X(val value: Y)

idea/testData/quickfix/removeAtFromAnnotationArgument/simple.kt.after

@@ -1,5 +1,4 @@
 // "Remove @ from annotation argument" "true"
-// ERROR: An annotation argument must be a compile-time constant
 
 annotation class Y()
 annotation class X(val value: Y)