Fix panic when no valid services are defined

[CapacitorSet]

Fixes #405.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@0c7cfc8). Click here to learn what that means.
The diff coverage is 0%.

@@            Coverage Diff            @@
##             master     #408   +/-   ##
=========================================
  Coverage          ?   41.68%           
=========================================
  Files             ?       78           
  Lines             ?     8796           
  Branches          ?        0           
=========================================
  Hits              ?     3667           
  Misses            ?     4704           
  Partials          ?      425

Impacted Files	Coverage Δ
server/honeytrap.go	3.15% <0%> (ø)

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