Introducing same two contacts not possible after self-destructing non-answered response to one-sided declined introduction

Under certain circumstances, an introduction can fail and leave the introducer in a state where they are not able to retry the introduction.

Situation to reproduce this: A introduces B and C with self-destructing messages enabled among A-B and A-C. At the time of the introduction being sent, C is offline to simulate a delay.

• introduction arrives at B
• 30 seconds pass
• C comes online
• introduction arrives at C
• another 30 seconds pass
• B didn't do anything, the introduction self-destructs, and auto-declines it
• A forwards the decline to C
• another 30 seconds pass
• C didn't do anything, the introduction self-destructs, but doesn't auto decline it because B already declined and the introduction can no longer succeed
• C didn't send a response and hence A cannot try again to introduce B and C, although it should. Also C has no way to respond to the introduction any longer to fix that

Test instructions:

• Variant 1
  • Let A introduce B and C, with self-destructing messages enabled among A and C but not necessarily enabled among A and B.
  • let B decline the introduction
  • observe that C receives the response from B
  • let the timer of the introduction expire at C
  • observe that A received a decline from both B and C
  • try to let A introduce B and C again. Make sure it is possible to actually send a new introduction that arrives at B and C
• Variant 2
  • Let A introduce B and C, with self-destructing messages enabled among A and C but not necessarily enabled among A and B.
  • let B accept the introduction
  • in this case, C does not receive any response from B
  • let the timer of the introduction expire at C
  • observe that A received an accept from B and a decline from C
  • try to let A introduce B and C again. Make sure it is possible to actually send a new introduction that arrives at B and C