Using local mysql for travis

[alaxalves]

Fixes #0000 (<=== Add issue number here)

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[codecov-io]

Codecov Report

Merging #3 into main will decrease coverage by 2.82%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main       #3      +/-   ##
==========================================
- Coverage   41.36%   38.53%   -2.83%     
==========================================
  Files          34       34              
  Lines        1308     1308              
==========================================
- Hits          541      504      -37     
- Misses        767      804      +37

Impacted Files	Coverage Δ
lib/exporter.rb	66.07% <0%> (-26%)	⬇️
app/models/map.rb	34.75% <0%> (-4.26%)	⬇️
app/models/warpable.rb	86.74% <0%> (+33.73%)	⬆️