rpc: use evm denom for tx fee

[fedekunze]

No description provided.

[codecov]

Codecov Report

Merging #181 (cabf38a) into main (1c06553) will decrease coverage by 6.73%.
The diff coverage is n/a.

❗ Current head cabf38a differs from pull request most recent head 1b1034a. Consider uploading reports for the commit 1b1034a to get more accurate results

@@            Coverage Diff             @@
##             main     #181      +/-   ##
==========================================
- Coverage   48.06%   41.33%   -6.74%     
==========================================
  Files          43       37       -6     
  Lines        2927     2240     -687     
==========================================
- Hits         1407      926     -481     
+ Misses       1450     1265     -185     
+ Partials       70       49      -21     

Impacted Files	Coverage Δ
app/test_helpers.go
crypto/ethsecp256k1/ethsecp256k1.go
app/app.go
app/ante/ante.go
app/ante/eth.go
app/export.go