T5406: webproxy op-mode command: add vrf support for blacklist update command

[nicolas-fort]

Change Summary

Webproxy: add vrf support for blacklist update command

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Migration from an old Vyatta component to vyos-1x, please link to related PR inside obsoleted component
• Other (please describe):

Related Task(s)

• https://vyos.dev/T5406

Component(s) name

webproxy

Proposed changes

Add vrf support for op-mode command update webproxy blacklists via command update webproxy blacklists vrf <vrf>

How to test

vyos@vyos:~$ update webproxy blacklists vrf TEST
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 27.2M  100 27.2M    0     0  4157k      0  0:00:06  0:00:06 --:--:-- 5803k
Uncompressing blacklist...
Processing file and database /opt/vyatta/etc/config/url-filtering/squidguard/db/examen_pix/domains
    [==================================================] 100 % done
Processing file and database /opt/vyatta/etc/config/url-filtering/squidguard/db/examen_pix/urls

Processing file and database /opt/vyatta/etc/config/url-filtering/squidguard/db/cleaning/domains
    [==================================================] 100 % done
Processing file and database /opt/vyatta/etc/config/url-filtering/squidguard/db/cleaning/urls
    [==================================================] 100 % done

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• I have run the components SMOKETESTS if applicable
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly