Merge pull request #7084 from remi-delmas-3000/make-contracts-methods-public

CONTRACTS: make `contracts.h` methods public.

Author: remi-delmas-3000

src/goto-instrument/contracts/contracts.h

@@ -141,6 +141,7 @@ class code_contractst
 
   std::unordered_set<irep_idt> summarized;
 
+public:
   /// Translates a function_pointer_obeys_contract_exprt into an assertion
   /// ```
   /// ASSERT function_pointer == contract;