Simplify/remove unused methods.

TestUtils.cpp

@@ -120,10 +120,6 @@ void ParallelClientBaseFixture::enumerateClients(std::function<void(Json::Value
 
 MoveNonceToTempDir::MoveNonceToTempDir()
 {
-	crypto::Nonce::setSeedFilePath(m_dir.path() + "/seed");
+	crypto::Nonce::seedFilePath(m_dir.path() + "/seed");
 }
 
-MoveNonceToTempDir::~MoveNonceToTempDir()
-{
-	crypto::Nonce::reset();
-}

TestUtils.h

@@ -82,7 +82,7 @@ struct JsonRpcFixture: public ClientBaseFixture
 struct MoveNonceToTempDir
 {
 	MoveNonceToTempDir();
-	~MoveNonceToTempDir();
+	~MoveNonceToTempDir() {}
 private:
 	TransientDirectory m_dir;
 };