chore: add Berty validator node in conf files

[D4ryl00]

This PR adds the Berty validator node in the config and README files for the test5 launch.

Contributors' checklist...

• Added new tests, or not needed, or not feasible
• Provided an example (e.g. screenshot) to aid review or the PR is self-explanatory
• Updated the official documentation or not needed
• No breaking changes were made, or a BREAKING CHANGE: xxx message was included in the description
• Added references to related issues and PRs
• Provided any useful hints for running manual tests

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.33%. Comparing base (cda327c) to head (28c63c7).

Additional details and impacted files

@@                          Coverage Diff                           @@
##           dev/zivkovicmilos/test5-deployment    #3095      +/-   ##
======================================================================
- Coverage                               63.33%   63.33%   -0.01%     
======================================================================
  Files                                     548      548              
  Lines                                   78680    78680              
======================================================================
- Hits                                    49835    49832       -3     
- Misses                                  25482    25484       +2     
- Partials                                 3363     3364       +1     

Flag	Coverage Δ
contribs/gnodev	61.16% <ø> (ø)
contribs/gnofaucet	14.82% <ø> (-0.95%)	⬇️
misc/genstd	79.72% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.