Fix CTS Verifier test for insecure RFCOMM connection.

Closing an RFCOMM server socket does not remove the corresponding
service record from the security database. However, the RFCOMM
channel becomes free for reuse. The next RFCOMM server socket will
therefore "inherit" the service record for the closed one if it
happens to reuse the same channel.

Bug: 22880207
Change-Id: Ida3fee49e5f40667d9992dc4c4442f9289adae9e