tls: flaky TestHandshakeConnectionCancelations/cancel_outgoing_connection

[marten-seemann]

https://github.com/libp2p/go-libp2p/runs/7157818312?check_suite_focus=true

  === RUN   TestHandshakeConnectionCancelations/cancel_outgoing_connection
      transport_test.go:178: 
          	Error Trace:	D:\a\go-libp2p\go-libp2p\p2p\security\tls\transport_test.go:178
          	Error:      	An error is expected but got nil.
          	Test:       	TestHandshakeConnectionCancelations/cancel_outgoing_connection
  === RUN   TestHandshakeConnectionCancelations/cancel_incoming_connection
  --- FAIL: TestHandshakeConnectionCancelations (2.08s)
      --- FAIL: TestHandshakeConnectionCancelations/cancel_outgoing_connection (0.26s)
      --- PASS: TestHandshakeConnectionCancelations/cancel_incoming_connection (0.01s)

[marten-seemann]

https://github.com/libp2p/go-libp2p/runs/7745508053?check_suite_focus=true

  === RUN   TestHandshakeConnectionCancelations
      transport_test.go:47: using a ECDSA key: QmViCTRxC6Hr755XJf9AVoZ7aHrmLE9SYsRijJhqQScXth
      transport_test.go:47: using a Ed25519 key: 12D3KooWNGdBE6geq4W7E9VA3EtnmNZUFzASHVFQdfjcH1EpTcCn
  === RUN   TestHandshakeConnectionCancelations/cancel_outgoing_connection
      transport_test.go:211: 
          	Error Trace:	/Users/runner/work/go-libp2p/go-libp2p/p2p/security/tls/transport_test.go:211
          	Error:      	Target error should be in err chain:
          	            	expected: "context canceled"
          	            	in chain: 
          	Test:       	TestHandshakeConnectionCancelations/cancel_outgoing_connection
  === RUN   TestHandshakeConnectionCancelations/cancel_incoming_connection
  --- FAIL: TestHandshakeConnectionCancelations (0.06s)
      --- FAIL: TestHandshakeConnectionCancelations/cancel_outgoing_connection (0.05s)
      --- PASS: TestHandshakeConnectionCancelations/cancel_incoming_connection (0.01s)