fix validator address prefix

[yihuang]

Description

staking keeper use sdk.Bech32PrefixValAddr directly, should use sdk.GetConfig().GetBech32ValidatorAddrPrefix().

closes: #XXXX

---

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• Targeted PR against correct branch (see CONTRIBUTING.md)
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• Code follows the module structure standards.
• Wrote unit and integration tests
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• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
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• Review Codecov Report in the comment section below once CI passes

[codecov]

Codecov Report

Merging #9212 (87c85f8) into master (0cbed20) will decrease coverage by 0.09%.
The diff coverage is 100.00%.

❗ Current head 87c85f8 differs from pull request most recent head dd0e5bc. Consider uploading reports for the commit dd0e5bc to get more accurate results

@@            Coverage Diff             @@
##           master    #9212      +/-   ##
==========================================
- Coverage   59.95%   59.86%   -0.10%     
==========================================
  Files         595      595              
  Lines       37357    37355       -2     
==========================================
- Hits        22397    22361      -36     
- Misses      12974    13011      +37     
+ Partials     1986     1983       -3     

Impacted Files	Coverage Δ
x/staking/keeper/val_state_change.go	51.91% <100.00%> (ø)
x/feegrant/types/msgs.go	0.00% <0.00%> (-72.10%)	⬇️
x/feegrant/types/basic_fee.go	65.00% <0.00%> (-10.00%)	⬇️
x/feegrant/client/testutil/suite.go	99.15% <0.00%> (-0.51%)	⬇️
x/feegrant/types/filtered_fee.go	0.00% <0.00%> (ø)
x/staking/keeper/keeper.go	56.66% <0.00%> (+1.49%)	⬆️

[amaury1093]

lgtm. Could you add a changelog entry?

@yihuang Just to confirm, this is not state/consensus-breaking, right (for non-hub chains)?

[yihuang]

lgtm. Could you add a changelog entry?

@yihuang Just to confirm, this is not state/consensus-breaking, right (for non-hub chains)?

I think it just fix a bug bring in by recent version v0.43.0-alpha1, for non-hub chains, it causes "CONSENSUS ERROR!!!". So I guess it is a consensus breaking change.

I checked that the bug is not there in v0.42.4, so do we need a changelog entry if the bug is not released yet?

[cyberbono3]

lgtm

[tac0turtle]

LGTM, thank you for the contribution