FIR: introduce flexible types pretty rendering for no arguments case

#KT-52020 Fixed

compiler/testData/loadJava/compiledJava/javaBean/DifferentGetterAndSetter.fir.txt

@@ -1,5 +1,5 @@
 public open class DifferentGetterAndSetter : R|kotlin/Any| {
-    public open fun setSomething(color: R|ft<kotlin/String, kotlin/String?>|): R|kotlin/Unit|
+    public open fun setSomething(color: R|kotlin/String!|): R|kotlin/Unit|
 
     public open fun getSomething(): R|kotlin/Int|
 

compiler/testData/loadJava/compiledJava/javaBean/JavaBeanVal.fir.txt

@@ -1,5 +1,5 @@
 public open class JavaBeanVal : R|kotlin/Any| {
-    public open fun getColor(): R|ft<kotlin/String, kotlin/String?>|
+    public open fun getColor(): R|kotlin/String!|
 
     public constructor(): R|test/JavaBeanVal|
 

compiler/testData/loadJava/compiledJava/javaBean/JavaBeanVar.fir.txt

@@ -1,7 +1,7 @@
 public open class JavaBeanVar : R|kotlin/Any| {
-    public open fun getColor(): R|ft<kotlin/String, kotlin/String?>|
+    public open fun getColor(): R|kotlin/String!|
 
-    public open fun setColor(string: R|ft<kotlin/String, kotlin/String?>|): R|kotlin/Unit|
+    public open fun setColor(string: R|kotlin/String!|): R|kotlin/Unit|
 
     public constructor(): R|test/JavaBeanVar|
 

compiler/testData/loadJava/compiledJava/javaBean/JavaBeanVarOfGenericType.fir.txt

@@ -1,8 +1,8 @@
-public open class JavaBeanVarOfGenericType<P : R|ft<kotlin/Any, kotlin/Any?>|> : R|kotlin/Any| {
+public open class JavaBeanVarOfGenericType<P : R|kotlin/Any!|> : R|kotlin/Any| {
     public open fun getCharacters(): R|ft<java/util/ArrayList<ft<P & Any, P?>>, java/util/ArrayList<ft<P & Any, P?>>?>|
 
     public open fun setCharacters(characters: R|ft<java/util/ArrayList<ft<P & Any, P?>>, java/util/ArrayList<ft<P & Any, P?>>?>|): R|kotlin/Unit|
 
-    public constructor<P : R|ft<kotlin/Any, kotlin/Any?>|>(): R|test/JavaBeanVarOfGenericType<P>|
+    public constructor<P : R|kotlin/Any!|>(): R|test/JavaBeanVarOfGenericType<P>|
 
 }

compiler/testData/loadJava/compiledJava/javaBean/TwoSetters.fir.txt

@@ -1,5 +1,5 @@
 public open class TwoSetters : R|kotlin/Any| {
-    public open fun setSize(size: R|ft<kotlin/String, kotlin/String?>|): R|kotlin/Unit|
+    public open fun setSize(size: R|kotlin/String!|): R|kotlin/Unit|
 
     public open fun setSize(size: R|kotlin/Int|): R|kotlin/Unit|