Optimize Imports tests: Switch to generated approach

Move test and rename test data
Delete unused testdata
Rewrite OptimizeImportOnFlyTest

idea/testData/editor/optimizeImports/JavaStaticField/JavaStaticField.kt

@@ -0,0 +1,6 @@
+import MyJavaClass
+import MyJavaClass.TEST
+
+fun main() {
+    TEST
+}