fix: Use fixed length hex for pointer at FwdCapabilityKey

[facundomedica]

Description

Use %#016p instead of %p to standardize across architectures. This will pad pointer addresses up to 16 chars (enough to do MaxUint64) and will remove the leading 0x in an effort to reduce the gas usage impact (so in the end we are only adding 3 bytes instead of 5).

0x14000cf4330 <- 13 bytes (old)
0000014000cf4330 <- 16 bytes (new)
0x0000014000cf4330 <- 18 bytes (what new would look like without #)

Closes: #11726

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Author Checklist

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I have...

• included the correct type prefix in the PR title
• added ! to the type prefix if API or client breaking change <- This IS a breaking change right?
• targeted the correct branch (see PR Targeting)
• provided a link to the relevant issue or specification
• followed the guidelines for building modules
• included the necessary unit and integration tests
• added a changelog entry to CHANGELOG.md
• included comments for documenting Go code
• updated the relevant documentation or specification
• reviewed "Files changed" and left comments if necessary
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I have...

• confirmed the correct type prefix in the PR title
• confirmed ! in the type prefix if API or client breaking change
• confirmed all author checklist items have been addressed
• reviewed state machine logic
• reviewed API design and naming
• reviewed documentation is accurate
• reviewed tests and test coverage
• manually tested (if applicable)

cc @marbar3778 @alexanderbez @ValarDragon

[ValarDragon]

LGTM! We have discussion in the issue for better longer term solutions (one of which seems like it may be simple if we understand correctly), but I see no reason to block this which is clearly correct and solves the immediate bug

[codecov]

Codecov Report

Merging #11737 (798c67e) into main (a8b3602) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main   #11737      +/-   ##
==========================================
+ Coverage   66.00%   66.02%   +0.02%     
==========================================
  Files         668      668              
  Lines       70695    70695              
==========================================
+ Hits        46659    46676      +17     
+ Misses      21345    21328      -17     
  Partials     2691     2691              

Impacted Files	Coverage Δ
x/capability/types/keys.go	100.00% <100.00%> (ø)
x/group/keeper/keeper.go	53.36% <0.00%> (-0.43%)	⬇️
x/distribution/simulation/operations.go	90.27% <0.00%> (+9.72%)	⬆️

[alexanderbez]

@AdityaSripal should this be backported to current releases (0.44.x, 0.45.x, 0.46.x)? This isn't state breaking AFAIk, as nodes can just restart safely.

[facundomedica]

@alexanderbez given that this changes the amount of gas used, and that gets used to calculate a hash that gets stored, maybe it is state breaking?

[alexanderbez]

Right...I forgot that happened, which is unfortunate. Why we charge gas for memory-based operations is questionable.