CompatHelper: bump compat for "DataStructures" to "0.18"

[github-actions]

This pull request changes the compat entry for the DataStructures package from 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17 to 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18.

This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry. It is your responsibility to make sure that your package tests pass before you merge this pull request.

[codecov-commenter]

Codecov Report

Merging #1476 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1476   +/-   ##
=======================================
  Coverage   89.17%   89.17%           
=======================================
  Files          39       39           
  Lines        4398     4398           
=======================================
  Hits         3922     3922           
  Misses        476      476           

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