config: fix parsing in WithConfig

[CapacitorSet]

Fixes warnings of unused keys when WithConfig is used.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@4bd11f8). Click here to learn what that means.
The diff coverage is 0%.

@@           Coverage Diff            @@
##             master    #362   +/-   ##
========================================
  Coverage          ?   8.56%           
========================================
  Files             ?     137           
  Lines             ?    9739           
  Branches          ?       0           
========================================
  Hits              ?     834           
  Misses            ?    8807           
  Partials          ?      98

Impacted Files	Coverage Δ
server/honeytrap.go	3.19% <0%> (ø)
services/services.go	12.5% <0%> (ø)

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[nl5887]

thx!