refactor: rename migrations from v42, v43, v{SDK} to v1, v2, v{Consensus}

[julienrbrt]

Description

While working on #13742, noticed an inconsistency in migrations naming.
This PR address that. Sort of continuation of #12579

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Author Checklist

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please add links to any relevant follow up issues.

I have...

• included the correct type prefix in the PR title
• added ! to the type prefix if API or client breaking change
• targeted the correct branch (see PR Targeting)
• provided a link to the relevant issue or specification
• followed the guidelines for building modules
• included the necessary unit and integration tests
• added a changelog entry to CHANGELOG.md
• included comments for documenting Go code
• updated the relevant documentation or specification
• reviewed "Files changed" and left comments if necessary
• confirmed all CI checks have passed

Reviewers Checklist

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your handle next to the items reviewed if you only reviewed selected items.

I have...

• confirmed the correct type prefix in the PR title
• confirmed ! in the type prefix if API or client breaking change
• confirmed all author checklist items have been addressed
• reviewed state machine logic
• reviewed API design and naming
• reviewed documentation is accurate
• reviewed tests and test coverage
• manually tested (if applicable)

[codecov]

Codecov Report

Merging #13772 (c988b7d) into main (39c5c07) will increase coverage by 0.62%.
The diff coverage is 74.41%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #13772      +/-   ##
==========================================
+ Coverage   56.05%   56.67%   +0.62%     
==========================================
  Files         659      636      -23     
  Lines       57393    54552    -2841     
==========================================
- Hits        32171    30918    -1253     
+ Misses      22628    21129    -1499     
+ Partials     2594     2505      -89     

Impacted Files	Coverage Δ
x/auth/keeper/migrations.go	0.00% <0.00%> (ø)
x/auth/migrations/v2/store.go	63.58% <ø> (ø)
x/auth/migrations/v3/store.go	78.57% <ø> (ø)
x/auth/migrations/v4/migrate.go	72.72% <ø> (ø)
x/auth/module.go	57.14% <0.00%> (ø)
x/authz/keeper/migrations.go	0.00% <0.00%> (ø)
x/authz/migrations/v2/keys.go	100.00% <ø> (ø)
x/authz/migrations/v2/store.go	70.45% <ø> (ø)
x/authz/module/module.go	17.94% <0.00%> (ø)
x/distribution/keeper/migrations.go	0.00% <0.00%> (ø)
... and 35 more

[tac0turtle]

Utack. Thanks for the cleanup