fix secp256k1 public key formatting

[noot]

Closes: #XXX

Description

use CompressPubkey and DecompressPubkey instead of FromECDSAPub and UnmarshalPubkey, fixes bech32 encoding error

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For contributor use:

• Targeted PR against correct branch (see CONTRIBUTING.md)
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the module structure standards.
• Wrote unit and integration tests
• Updated relevant documentation (docs/) or specification (x/<module>/spec/)
• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
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For admin use:

• Added appropriate labels to PR (ex. WIP, R4R, docs, etc)
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• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)

[codecov]

Codecov Report

Merging #501 into account-pretty will decrease coverage by 0.10%.
The diff coverage is 42.85%.

@@                Coverage Diff                 @@
##           account-pretty     #501      +/-   ##
==================================================
- Coverage           71.82%   71.72%   -0.11%     
==================================================
  Files                  40       40              
  Lines                2673     2677       +4     
==================================================
  Hits                 1920     1920              
- Misses                614      616       +2     
- Partials              139      141       +2     

Impacted Files	Coverage Δ
crypto/secp256k1.go	74.35% <42.85%> (-8.50%)	⬇️

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