fix: removing bug introduced to mp_getddl and adding a test to prevent regression

tests/base/mp_getddl.test.sas

@@ -0,0 +1,23 @@
+/**
+  @file
+  @brief Testing mp_getddl.sas macro
+
+  <h4> SAS Macros </h4>
+  @li mp_getddl.sas
+  @li mp_assert.sas
+
+**/
+
+data test(index=(pk=(x y)/unique /nomiss));
+  x=1;
+  y='blah';
+  label x='blah';
+run;
+proc sql; describe table &syslast;
+%mp_getddl(work,test,flavour=tsql,showlog=YES)
+
+%mp_assert(
+  iftrue=(&syscc=0),
+  desc=mp_getddl runs without errors,
+  outds=work.test_results
+)