[FIR] Fix computeTypeArguments() & add diagnostic for type args

compiler/fir/analysis-tests/testData/resolve/diagnostics/projectionsOnNonClassTypeArguments.kt

@@ -0,0 +1,8 @@
+class A<in T, out K>
+class B
+
+fun test() {
+    val a1 = A<<!PROJECTION_ON_NON_CLASS_TYPE_ARGUMENT!>in Int<!>, <!PROJECTION_ON_NON_CLASS_TYPE_ARGUMENT!>out B<!>>()
+    val a2 = A<Int, B>()
+    val a3 = A<<!PROJECTION_ON_NON_CLASS_TYPE_ARGUMENT!>*<!>, <!PROJECTION_ON_NON_CLASS_TYPE_ARGUMENT!>*<!>>()
+}

compiler/fir/analysis-tests/testData/resolve/diagnostics/projectionsOnNonClassTypeArguments.txt

@@ -0,0 +1,18 @@
+FILE: projectionsOnNonClassTypeArguments.kt
+    public final class A<in T, out K> : R|kotlin/Any| {
+        public constructor<in T, out K>(): R|A<T, K>| {
+            super<R|kotlin/Any|>()
+        }
+
+    }
+    public final class B : R|kotlin/Any| {
+        public constructor(): R|B| {
+            super<R|kotlin/Any|>()
+        }
+
+    }
+    public final fun test(): R|kotlin/Unit| {
+        lval a1: R|A<kotlin/Int, B>| = R|/A.A|<in R|kotlin/Int|, out R|B|>()
+        lval a2: R|A<kotlin/Int, B>| = R|/A.A|<R|kotlin/Int|, R|B|>()
+        lval a3: R|A<kotlin/Any?, kotlin/Any?>| = R|/A.A|<*, *>()
+    }