fix(travis): fix heroku stage

[Domainv]

PR Checklist

Before creating new PR, please take a look at checklist below to make sure that you've done everything that needs to be done before we can merge it.

• read and followed the CONTRIBUTING.md guide.
• built and tested the changes locally.
• added/updated tests.
• added/updated API documentation.
• added/updated demos.

[codecov]

Codecov Report

Merging #4820 into development will increase coverage by 0.05%.
The diff coverage is n/a.

@@               Coverage Diff               @@
##           development    #4820      +/-   ##
===============================================
+ Coverage        74.35%   74.41%   +0.05%     
===============================================
  Files              204      204              
  Lines             7168     7168              
  Branches          1457     1457              
===============================================
+ Hits              5330     5334       +4     
+ Misses            1435     1432       -3     
+ Partials           403      402       -1

Impacted Files	Coverage Δ
src/chronos/i18n/cs.ts	86.44% <0%> (+1.69%)	⬆️
src/chronos/i18n/sk.ts	82.97% <0%> (+2.12%)	⬆️
src/chronos/i18n/pl.ts	72.22% <0%> (+2.77%)	⬆️
src/chronos/i18n/pt-br.ts	100% <0%> (+25%)	⬆️

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