Change the fallback priority mechanism to be based on gas price

[yihuang]

Description

port the changes from here: cosmos/cosmos-sdk#12953

should have no effect on existing chains if London hardfork is enabled.

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[codecov]

Codecov Report

Merging #1289 (5237da9) into main (efc5a15) will increase coverage by 0.00%.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1289   +/-   ##
=======================================
  Coverage   55.15%   55.16%           
=======================================
  Files         105      105           
  Lines        9607     9608    +1     
=======================================
+ Hits         5299     5300    +1     
  Misses       4043     4043           
  Partials      265      265           

Impacted Files	Coverage Δ
app/ante/fee_checker.go	96.77% <100.00%> (+0.03%)	⬆️

[fedekunze]

ACK

[facs95]

uTACK

[AlphaMale1st]

[AlphaMale1st]

What should I change the price to ?