fix: add missing subspaces authz migration

[RiccardoM]

Description

This PR adds the x/subspaces authorization migrations that was missing from v4.2.0.

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[codecov]

Codecov Report

Merging #981 (b79173e) into master (987ec5d) will decrease coverage by 0.00%.
The diff coverage is 80.00%.

❗ Current head b79173e differs from pull request most recent head 36324b7. Consider uploading reports for the commit 36324b7 to get more accurate results

@@            Coverage Diff             @@
##           master     #981      +/-   ##
==========================================
- Coverage   80.53%   80.53%   -0.01%     
==========================================
  Files         172      174       +2     
  Lines       15244    15274      +30     
==========================================
+ Hits        12277    12301      +24     
- Misses       2440     2444       +4     
- Partials      527      529       +2     

Impacted Files	Coverage Δ
x/subspaces/legacy/v4/store.go	76.00% <76.00%> (ø)
x/subspaces/legacy/v2/codec.go	100.00% <100.00%> (ø)

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[dadamu]

Some tests are error.

[RiccardoM]

Some tests are error.

Fixed