Add support for TM secp256k1

[amaury1093]

Description

closes: #7529

depends on:

• Replace tmcrypto.PubKey by our own cryptotypes.PubKey #7419

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Before we can merge this PR, please make sure that all the following items have been
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write a little note why.

• 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
• Re-reviewed Files changed in the Github PR explorer
• Review Codecov Report in the comment section below once CI passes

[codecov]

Codecov Report

Merging #7838 (1fb8020) into master (c0d7233) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #7838   +/-   ##
=======================================
  Coverage   54.15%   54.15%           
=======================================
  Files         612      612           
  Lines       38985    38985           
=======================================
  Hits        21114    21114           
  Misses      15701    15701           
  Partials     2170     2170