Improved test resilience

[tzaeschke]

Add proper warnings if a daemon or control server is running locally.

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This change is 

[codecov]

Codecov Report

Attention: Patch coverage is 90.90909% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 77.41%. Comparing base (8fce1b4) to head (cdb3963).

Files	Patch %	Lines
src/main/java/org/scion/jpan/ScionUtil.java	90.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff            @@
##             master      #50   +/-   ##
=========================================
  Coverage     77.41%   77.41%           
- Complexity      429      430    +1     
=========================================
  Files            27       28    +1     
  Lines          2063     2063           
  Branches        274      274           
=========================================
  Hits           1597     1597           
+ Misses          350      349    -1     
- Partials        116      117    +1     

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