fix: windows file permission take 2 (#503)

* Fix windows permission error when dumping model file

* Properly use file context when dumping model

Author: KristijanFaust-OET

linopy/remote/oetc.py

@@ -495,12 +495,10 @@ def solve_on_oetc(self, model):  # type: ignore
         """
         try:
             # Save model to temporary file and upload
-            model_dump_path = None
             with tempfile.NamedTemporaryFile(prefix="linopy-", suffix=".nc") as fn:
-                model_dump_path = fn.name
-
-            model.to_netcdf(model_dump_path)
-            input_file_name = self._upload_file_to_gcp(fn.name)
+                fn.file.close()
+                model.to_netcdf(fn.name)
+                input_file_name = self._upload_file_to_gcp(fn.name)
 
             # Submit job and wait for completion
             job_uuid = self._submit_job_to_compute_service(input_file_name)