fix: what bandit and the remaining lint rules found

- Long shell command lines are split into adjacent string literals.
- get_os_users: a first loop over /etc/group filled a map nobody read;
  it is gone, the output is unchanged.
- The five except Exception: pass now log at debug level (B110), so a
  swallowed failure leaves a trace.
- nosec for the staging path on the device (B108) and the sudo hint
  message (B105); both are false positives.
- tests: raise ... from exc, unused loop variable.

tests/test_fix_templates.py

@@ -188,7 +188,7 @@ def test_every_annotation_resolves():
     import inspect
     import typing
 
-    for name, member in inspect.getmembers(LinuxDriver, inspect.isfunction):
+    for _name, member in inspect.getmembers(LinuxDriver, inspect.isfunction):
         if member.__module__ == "napalm_linux.linux":
             typing.get_type_hints(member)