Remove MATCH SIMPLE from my.sql

[k1LoW]

see https://dev.mysql.com/doc/refman/8.0/en/constraint-foreign-key.html

[codecov]

Codecov Report

Merging #140 into master will decrease coverage by 1.16%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #140      +/-   ##
==========================================
- Coverage   69.32%   68.15%   -1.17%     
==========================================
  Files          12       12              
  Lines        2657     2657              
==========================================
- Hits         1842     1811      -31     
- Misses        624      661      +37     
+ Partials      191      185       -6

Impacted Files	Coverage Δ
datasource/datasource.go	20.85% <0%> (-19.02%)	⬇️

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