cmd: check for errors on log websockets

[didil]

🎟️ Ticket(s): Closes #526

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👷 Changes

add error checking on client.LogsWebSocket + test

🔦 Testing Instructions

make test

[bobheadxi]

looks good, thanks! Just one minor comment

[codecov]

Codecov Report

Merging #533 into master will increase coverage by 0.03%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #533      +/-   ##
==========================================
+ Coverage   56.22%   56.25%   +0.03%     
==========================================
  Files          60       60              
  Lines        2983     2985       +2     
==========================================
+ Hits         1677     1679       +2     
  Misses       1098     1098              
  Partials      208      208

Impacted Files	Coverage Δ
client/client.go	70.72% <100%> (+0.25%)	⬆️

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[bobheadxi]

thank! 🎉

[bobheadxi]

@didil looks like Windows returns a different error when the websocket connection fails:
https://ci.appveyor.com/project/ubclaunchpad/inertia/builds/22186666

--- FAIL: TestLogsWebsocketNoDaemon (1.02s)
    client_test.go:378: 
        	Error Trace:	client_test.go:378
        	Error:      	"failed to connect to daemon at 127.0.0.1:1150: dial tcp 127.0.0.1:1150: connectex: No connection could be made because the target machine actively refused it." does not contain "connect: connection refused"
        	Test:       	TestLogsWebsocketNoDaemon
FAIL
coverage: 55.6% of statements
FAIL	github.com/ubclaunchpad/inertia/client	3.164s

unfortunately I can't seem to get Appveyor to trigger on our end for forked repositories, so a Windows test run was never made for this PR, and the one for master just failed. Do you mind putting in a PR to address this?