Use go1.13 for CI again

[cuonglm]

PR #1157 used go1.12 temporary for Dockerfile, to mitigate golang/go#34282. The backport issue was merged golang/go#34285 and go1.13.1 go1.13.3 is now released. so we can use go1.13 again.

Close #1153

[codecov-io]

Codecov Report

Merging #1177 into master will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1177      +/-   ##
==========================================
+ Coverage   73.59%   73.61%   +0.01%     
==========================================
  Files         145      145              
  Lines       10575    10575              
==========================================
+ Hits         7783     7785       +2     
+ Misses       2333     2331       -2     
  Partials      459      459

Impacted Files	Coverage Δ
stats/cloud/collector.go	71.66% <0%> (+0.65%)	⬆️

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[mstoykov]

Isn't go1.13.1 just a security fix release? The milestone seems to suggest this ... As far as I can see we need to wait for 1.13.2

[cuonglm]

Isn't go1.13.1 just a security fix release? The milestone seems to suggest this ... As far as I can see we need to wait for 1.13.2

Ah yes, my bad.

[na--]

Pre-aproving this, so it can be merged when 1.13.2 comes out

[cuonglm]

go1.13.3 is released with proper fixes, we can use go1.13 for CI now.

[mstoykov]

Again I have the problem that because we don't specify the exact version of golang to be used, I can't now know if the package was updated and even if it's in dockerhub if it's not cached by circleci.
I just reran the test and it download 1.13.1 ... again ... so we wait :)

[cuonglm]

Again I have the problem that because we don't specify the exact version of golang to be used, I can't now know if the package was updated and even if it's in dockerhub if it's not cached by circleci.
I just reran the test and it download 1.13.1 ... again ... so we wait :)

It should get the latest minor version of go1.13, IIRC.

[cuonglm]

Again I have the problem that because we don't specify the exact version of golang to be used, I can't now know if the package was updated and even if it's in dockerhub if it's not cached by circleci.
I just reran the test and it download 1.13.1 ... again ... so we wait :)

It should get the latest minor version of go1.13, IIRC.

I recheck, circleci docker hub golang image is not updated, so we have to wait them upgrading.

[na--]

Yet another reason to get out of CircleCI (#959) - I see no reason why we should use some strange custom Go docker image and not the official ones... 😕

[cuonglm]

@mstoykov @na-- circleci updated the golang image to 1.13.3.