JetDiagnosticsTest migrated to TestGenerator

- test data files renamed from *.jet to *.kt

compiler/testData/diagnostics/tests/checkArguments/kt1940.kt

@@ -0,0 +1,9 @@
+//KT-1940 Exception while repeating named parameters
+package kt1940
+
+fun foo(<!UNUSED_PARAMETER!>i<!>: Int) {}
+
+fun test() {
+    foo(1, <!ARGUMENT_PASSED_TWICE, MIXING_NAMED_AND_POSITIONED_ARGUMENTS!>i<!> = 2) //exception
+    foo(i = 1, <!ARGUMENT_PASSED_TWICE!>i<!> = 2) //exception
+}