Remove temp model archive after extraction

Without this change every time a model is downloaded
it leaks a file in the temp directory.

spleeter/model/provider/github.py

@@ -16,6 +16,7 @@
 
 import hashlib
 import tarfile
+import os
 
 from tempfile import NamedTemporaryFile
 
@@ -96,6 +97,7 @@ class GithubModelProvider(ModelProvider):
         with requests.get(url, stream=True) as response:
             response.raise_for_status()
             archive = NamedTemporaryFile(delete=False)
+            try:
                 with archive as stream:
                     # Note: check for chunk size parameters ?
                     for chunk in response.iter_content(chunk_size=8192):
@@ -107,4 +109,6 @@ class GithubModelProvider(ModelProvider):
                 get_logger().info('Extracting downloaded %s archive', name)
                 with tarfile.open(name=archive.name) as tar:
                     tar.extractall(path=path)
+            finally:
+                os.unlink(archive.name)
         get_logger().info('%s model file(s) extracted', name)