remove unused dependency on Compat.jl

[ranocha]

This dependency has already been removed in #221. It was added again in #224. However, it has not been removed when finally updating the required Julia version in #328.

This fixes an issue found after adding a Downgrade check to RootedTrees.jl in SciML/RootedTrees.jl#192 and SciML/RootedTrees.jl#194.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.77%. Comparing base (1c17407) to head (3f5139d).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #350      +/-   ##
==========================================
- Coverage   86.96%   86.77%   -0.20%     
==========================================
  Files          11       11              
  Lines         514      514              
==========================================
- Hits          447      446       -1     
- Misses         67       68       +1     

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[lgoettgens]

Good catch, thanks! However, as this just affects the Aqua master branch, it is highly unlikely that this PR fixes any issue you encountered using Aqua

[ranocha]

Thanks a lot for merging this so quickly. When will there ever be a new release of Aqua.jl including this fix?

[lgoettgens]

I don't understand how this should fix anything on any current release of Aqua. Iiuc, this should have only affected the master branch. For the 1.0 progress, see #310

[ChrisRackauckas]

Why would this need to wait for a v1.0? This should just be a really little patch.

[lgoettgens]

Why would this need to wait for a v1.0? This should just be a really little patch.

This patch is not applicable to the release-0.8 branch as that still supports all the way back to julia 1.0, and thus needs Compat.
If you could tell me what specific problem you are trying to fix here (ideally with the Aqua version used), I can try to understand you position and give a suggestion for a path forward.

[ranocha]

The Downgrade CI jobs added to a few repositories fail because of this (see the links in the first post of this PR). Some dependencies seem to introduce old versions of Compat somewhere and we do not want to maintain different versions of Aqua.jl in the tests.

[lgoettgens]

Looking at https://github.com/SciML/RootedTrees.jl/actions/runs/16923512413/job/47954604808#step:6:52, it seems that something in your project is requesting Compat.jl v2 (which is very old), while Aqua (the v0.8.x release series) needs Compat.jl v3 or v4. This does not seems to be Aqua's fault.

[ranocha]

Well, it would be fine if we could use a new version of Aqua.jl that does not depend on Compat.jl anymore. That's what motivated me to create this PR.