fix: what bandit and the remaining lint rules found

- The six except Exception: pass (REST logout, the extra-ports lookup, the
  per-port detail in get_interfaces, closing CLI and REST sessions) now log
  at debug level (B110), so a swallowed failure leaves a trace.
- nosec for comparing a reported address with 0.0.0.0 (B104) and for the
  empty password field of get_users (B105, now a named constant); both are
  false positives.
- A long error message is split into adjacent f-strings; the unused ARP
  entry type is named _entry_type.
- tests: the failed-open test expects ConnectionException instead of any
  Exception; raise ... from exc.

napalm_procurve/parsers.py

@@ -9,6 +9,9 @@ backends.
 
 import re
 
+#: get_users' password field: the switch never shows a password, so it stays empty.
+_PASSWORD_NOT_SHOWN = ""  # nosec B105
+
 # ---------------------------------------------------------------------------
 # MAC address helpers
 # ---------------------------------------------------------------------------
@@ -330,7 +333,8 @@ def parse_ip_interfaces(output: str) -> dict[str, dict]:
         # Single VLAN output (no header): detect from "IP Address" line
         if re.search(r"IP\s+Address\s*:", line, re.I):
             ip = line.split(":", 1)[-1].strip()
-            if ip and ip not in ("0.0.0.0", ""):
+            # An unset address reported by the switch, not a bind address.
+            if ip and ip != "0.0.0.0":  # nosec B104
                 current_ip = ip
                 if not current_vlan:
                     current_vlan = "VLAN1"
@@ -375,7 +379,7 @@ def parse_arp_table(output: str) -> list[dict]:
         m = _ARP_RE.search(line)
         if not m:
             continue
-        ip, mac, entry_type, port = (m.group(1), m.group(2), m.group(3), m.group(4) or "")
+        ip, mac, _entry_type, port = (m.group(1), m.group(2), m.group(3), m.group(4) or "")
         table.append(
             {
                 "interface": port,
@@ -665,7 +669,7 @@ def parse_users(output: str) -> dict[str, dict]:
             priv = 1
         users[uname] = {
             "level": priv,
-            "password": "",
+            "password": _PASSWORD_NOT_SHOWN,
             "sshkeys": [],
         }
     return users