Fix greek language to follow ELOT 743 standard

[imikod]

No description provided.

[codecov]

Codecov Report

Merging #70 (d76d2b4) into master (6d7c3ee) will not change coverage.
The diff coverage is n/a.

❗ Current head d76d2b4 differs from pull request most recent head a5b6e62. Consider uploading reports for the commit a5b6e62 to get more accurate results

Additional details and impacted files

@@            Coverage Diff            @@
##            master       #70   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            2         2           
  Lines          147       138    -9     
=========================================
- Hits           147       138    -9     

Impacted Files	Coverage Δ
languages_substitution.go	100.00% <ø> (ø)
slug.go	100.00% <0.00%> (ø)