Simplified lifetime management of tests

- Addresses Sonarcloud issues:
  - Rewrite the code so that you no longer need this "delete".
  - Make the type of this variable a reference-to-const.

test/unit/unit.cc

@@ -250,8 +250,8 @@ int main(int argc, char **argv) {
     }
 
     for (auto& [filename, tests] : test) {
-        total += tests->size();
-        for (auto t : *tests) {
+        total += tests.size();
+        for (auto &t : tests) {
             ModSecurityTestResults<UnitTest> r;
 
             if (!test.m_automake_output) {
@@ -311,12 +311,5 @@ int main(int argc, char **argv) {
         }
     }
 
-    for (auto a : test) {
-        auto vec = a.second;
-        for(auto t : *vec)
-            delete t;
-        delete vec;
-    }
-
     return failed;
 }