database: Add missing virtual destructors for some classes

database/categorydao.h

@@ -15,6 +15,7 @@ class CategoryDao
 	virtual std::optional<Category> find(std::string name) = 0;
 	virtual void deleteCategory(std::string name) = 0;
 	virtual std::vector<Page> fetchMembers(std::string name, QueryOption o) = 0;
+	virtual ~CategoryDao() = default;
 };
 
 #endif // CATEGORYDAO_H

database/permissionsdao.h

@@ -9,6 +9,7 @@ class PermissionsDao
 	PermissionsDao();
 	virtual std::optional<Permissions> find(std::string pagename, std::string username) = 0;
 	virtual void save(std::string pagename, std::string username, Permissions perms) = 0;
+	virtual ~PermissionsDao() = default;
 };
 
 #endif // PERMISSIONSDAO_H

database/sqlitedao.h

@@ -37,6 +37,8 @@ class SqliteDao
 
 	bool execBool(sqlite::database_binder &binder) const;
 	int execInt(sqlite::database_binder &binder) const;
+
+	virtual ~SqliteDao() = default;
 };
 
 #endif // SQLITEDAO_H