added test cases for cyrcular definitions

testsuite/compiler/check/cyclic/opers/TestOpers.gf

@@ -0,0 +1,10 @@
+resource TestOpers = {
+
+flags
+  optimize=noexpand;
+
+oper
+  A : Str = B ;
+  B : Str = A ;
+
+}

testsuite/compiler/check/cyclic/opers/test.gfs

@@ -0,0 +1 @@
+i testsuite/compiler/check/cyclic/opers/TestOpers.gf

testsuite/compiler/check/cyclic/opers/test.gfs.gold

@@ -0,0 +1,4 @@
+␍
+␍
+checking module TestOpers␍
+   circular definitions: A B␍