Make it optional to skip resultpage for new key

This is intended for organisations who have clear
processes to lead their users most simply through
the key creation process.

The old behavior is still the default.

GnuPG-Bug-Id: T5181
2 jobs for master in 19 minutes and 16 seconds (queued for 96 minutes and 47 seconds)
Status Job ID Name Coverage
  Build
passed #84617
build_clazy_clang_tidy

00:12:59

passed #84616
linux kf5-qt5 qt5.15

00:06:17

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