Make sure we have write permission if we want to import packages

This is not perfect as the permissions might change between this check
and the actual system state writing.

libdnf5/system/state.cpp

@@ -23,6 +23,7 @@ along with libdnf.  If not, see <https://www.gnu.org/licenses/>.
 
 #include "libdnf5/utils/bgettext/bgettext-mark-domain.h"
 #include "libdnf5/utils/fs/file.hpp"
+#include "libdnf5/utils/fs/temp.hpp"
 
 #include <libdnf5/comps/group/package.hpp>
 #include <toml.hpp>
@@ -247,6 +248,13 @@ State::State(const std::filesystem::path & path) : path(path) {
 
 
 bool State::packages_import_required() {
+    // Importing will require write permission
+    try {
+        utils::fs::TempFile(path, "permissions-test");
+    } catch (const FileSystemError & e) {
+        return false;
+    }
+
     // TODO(mblaha) - detect by absence of toml file instead of empty nevra_states?
     // Because even empty nevra_states is a valid state.
     return nevra_states.empty();