Loosen DataStructure compat versions

[rofinn]

No description provided.

[codecov]

Codecov Report

Merging #13 (d7ebff1) into main (cdb02ad) will increase coverage by 0.86%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main      #13      +/-   ##
==========================================
+ Coverage   92.68%   93.54%   +0.86%     
==========================================
  Files           3        3              
  Lines          82       62      -20     
==========================================
- Hits           76       58      -18     
+ Misses          6        4       -2     

Impacted Files	Coverage Δ
src/session.jl	100.00% <0.00%> (ø)
src/Checkpoints.jl	88.88% <0.00%> (+0.42%)	⬆️
src/handler.jl	90.90% <0.00%> (+1.25%)	⬆️

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[rofinn]

AFAICT, DefaultDict wasn't changed during that major release. Ran the tests locally with it pinned to 0.17.20 it still passed.