maintainers/hydra-eval-failures: catch fetching maintainers

Fails with some i686-linux build failures

maintainers/scripts/hydra-eval-failures.py

@@ -31,6 +31,7 @@ EVAL_FILE = {
 
 
 def get_maintainers(attr_name):
+    try:
         nixname = attr_name.split('.')
         meta_json = subprocess.check_output([
             'nix-instantiate',
@@ -43,6 +44,8 @@ def get_maintainers(attr_name):
         meta = json.loads(meta_json)
         if meta.get('maintainers'):
             return [MAINTAINERS[name] for name in meta['maintainers'] if MAINTAINERS.get(name)]
+    except:
+       return []
 
 
 @click.command()