change request id to be bytes

Change-Id: If980f23259a31acc59d17e3115a27320e94dcacb
diff --git a/src/detail/ca-sqlite.hpp b/src/detail/ca-sqlite.hpp
index 5d12188..f0ffe1f 100644
--- a/src/detail/ca-sqlite.hpp
+++ b/src/detail/ca-sqlite.hpp
@@ -43,7 +43,7 @@
    * @throw if request cannot be fetched from underlying data storage
    */
   CaState
-  getRequest(const std::string& requestId) override;
+  getRequest(const RequestID& requestId) override;
 
   /**
    * @throw if there is an existing request with the same request ID
@@ -55,7 +55,7 @@
   updateRequest(const CaState& request) override;
 
   void
-  deleteRequest(const std::string& requestId) override;
+  deleteRequest(const RequestID& requestId) override;
 
   std::list<CaState>
   listAllRequests() override;