Set the denom metadata for the cosmoshub in the stargate migration

[zmanian]

Set the Cosmos Hub ATOM metadata as required by
cosmos/cosmos-sdk#8417

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[codecov]

Codecov Report

Merging #564 (55c5f14) into main (1a98272) will decrease coverage by 0.21%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main     #564      +/-   ##
==========================================
- Coverage   11.58%   11.37%   -0.22%     
==========================================
  Files           8        8              
  Lines         673      686      +13     
==========================================
  Hits           78       78              
- Misses        586      599      +13     
  Partials        9        9