Remove constantly updating value from custom SNMP OID

[syn-bit]

Adding a custom SNMP OID means having a different "expression " line each time the config is pulled. Add a rule to remove the expression value.

EEM code to generate the custom SNMP OID is:

event manager applet TotalNatTranslations event timer watchdog time 300 maxrun 60 action 010 cli command "enable" action 020 cli command "configure terminal" action 030 cli command "do-exec show ip nat translations total" action 040 regexp "^.+\s([0-9]+)" "$_cli_result" match total_translations action 050 cli command "snmp mib expression owner nat name 1" action 060 if $_regexp_result eq "1" action 070 cli command "expression $total_translations" action 080 else action 090 cli command "expression 0" action 100 cli command "exit" action 110 end

The resulting configuration block is:

snmp mib expression owner nat name 1 description Total active translations value type integer32 expression 1234 !

After this commit the resulting configuration block is:

snmp mib expression owner nat name 1 description Total active translations value type integer32 expression !

Pre-Request Checklist

• [ ] Passes rubocop code analysis (try rubocop --auto-correct)
• [ ] Tests added or adapted (try rake test)
• [ ] Changes are reflected in the documentation
• [ ] User-visible changes appended to CHANGELOG.md

Description