feat!: implement expired subspace fee grant deletion

[dadamu]

Description

This PR implements expired subspace fee grant deletion mentioned in ADR-017.

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[codecov]

Codecov Report

Patch coverage: 89.47% and project coverage change: -0.46 ⚠️

Comparison is base (275eee9) 80.95% compared to head (ce8ef22) 80.49%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1198      +/-   ##
==========================================
- Coverage   80.95%   80.49%   -0.46%     
==========================================
  Files         215      218       +3     
  Lines       18062    18289     +227     
==========================================
+ Hits        14622    14722     +100     
- Misses       2829     2955     +126     
- Partials      611      612       +1     

Impacted Files	Coverage Δ
x/subspaces/module.go	12.58% <0.00%> (ø)
x/subspaces/types/models_feegrant.go	78.57% <61.53%> (-0.38%)	⬇️
x/subspaces/abci.go	100.00% <100.00%> (ø)
x/subspaces/keeper/feegrant.go	94.32% <100.00%> (+2.92%)	⬆️
x/subspaces/legacy/v7/store.go	100.00% <100.00%> (ø)
x/subspaces/simulation/decoder.go	100.00% <100.00%> (ø)

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[RiccardoM]

These lines can be combined

Suggested change

	allowanceKey := allowancePrefix
	allowanceKey = append(allowanceKey, iterator.Key()...)
	allowanceKey := append(allowancePrefix, iterator.Key()...)

[dadamu]

It would cause the linter error: appendAssign: append result not assigned to the same slice (gocritic).
https://github.com/desmos-labs/desmos/actions/runs/5552100585/jobs/10139013465#step:5:146

[RiccardoM]

What about something like this?

allowanceKey := append([]byte(allowanceKey...), iterator.Key()...)

[dadamu]

It would be another linter problem:
x/subspaces/legacy/v7/store.go:33:33: unnecessary conversion (unconvert) allowanceKey := append([]byte(allowancePrefix), iterator.Key()...)

[RiccardoM]

Ok then we can leave it as it is

[dadamu]

I found the similar codes in profile grpc_query which uses append([]byte(nil), prefix) pattern. I think we can apply it.

https://github.com/desmos-labs/desmos/blob/master/x/profiles/keeper/grpc_query.go#L179

Updated