p2p: fix unstable test TestServerWrapperDelayed

[liuzix]

What problem does this PR solve?

[2021-11-03T03:03:49.175Z] [2021/11/03 11:01:57.701 +08:00] [INFO] [server_wrapper_test.go:49] ["error received"] [error="rpc error: code = Canceled desc = context canceled"]

[2021-11-03T03:03:49.175Z] --- FAIL: TestServerWrapperDelayed (0.13s)

[2021-11-03T03:03:49.175Z]     server_wrapper_test.go:185: FAIL:	OnNewMessage(*p2p.MessagePacket)

[2021-11-03T03:03:49.175Z]         		at: [server_wrapper_test.go:165]

[2021-11-03T03:03:49.175Z]     server_wrapper_test.go:185: FAIL: 0 out of 1 expectation(s) were met.

[2021-11-03T03:03:49.175Z]         	The code you are testing needs to make 1 more call(s).

[2021-11-03T03:03:49.175Z]         	at: [server_wrapper_test.go:185]

[2021-11-03T03:03:49.175Z] FAIL

What is changed and how it works?

• This test case should be considered passed only if it does not panic, because we should not require a cancelled gRPC server to handle the request before it exits.

Check List

Tests

• Unit test

Release note

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

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• 3AceShowHand
• asddongmen

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[liuzix]

/run-leak-tests

[amyangfei]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 1c64543

[codecov-commenter]

Codecov Report

Merging #3250 (1c64543) into master (de2fca8) will decrease coverage by 0.0698%.
The diff coverage is n/a.

@@               Coverage Diff                @@
##             master      #3250        +/-   ##
================================================
- Coverage   56.7226%   56.6528%   -0.0699%     
================================================
  Files           214        214                
  Lines         22915      22915                
================================================
- Hits          12998      12982        -16     
- Misses         8604       8622        +18     
+ Partials       1313       1311         -2