[FIR] Throw REDECLARATION for duplicated type parameters in declarations

compiler/testData/diagnostics/tests/redeclarations/RedeclaredTypeParameters.fir.kt

@@ -1,6 +1,6 @@
-fun <T, T> Pair() {}
+fun <<!REDECLARATION!>T<!>, <!REDECLARATION!>T<!>> Pair() {}
 
-class P<T, T> {}
+class P<<!REDECLARATION!>T<!>, <!REDECLARATION!>T<!>> {}
 
-val <T, T> T.foo : Int
-    get() = 1
+val <<!REDECLARATION!>T<!>, <!REDECLARATION!>T<!>> T.foo : Int
+    get() = 1

compiler/testData/diagnostics/tests/redeclarations/interfaceTypeParameters.fir.kt

@@ -1,6 +0,0 @@
-interface Test1<T, T>
-interface Test2<X, Y, X>
-
-class Outer<T> {
-    interface TestNested<T>
-}

compiler/testData/diagnostics/tests/redeclarations/interfaceTypeParameters.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 interface Test1<<!REDECLARATION!>T<!>, <!REDECLARATION!>T<!>>
 interface Test2<<!REDECLARATION!>X<!>, Y, <!REDECLARATION!>X<!>>