docker: disable public signet node

[hulxv]

Close #712

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 78.15%. Comparing base (776b75d) to head (5e56b42).
⚠️ Report is 86 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #716      +/-   ##
==========================================
+ Coverage   68.87%   78.15%   +9.28%     
==========================================
  Files          35       49      +14     
  Lines        4932    15251   +10319     
==========================================
+ Hits         3397    11920    +8523     
- Misses       1535     3331    +1796     

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[mojoX911]

Ack