optimized staking weight value

[zjg555543]

• 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.

• [ ] Wrote tests

• [ ] Updated relevant documentation (docs/)

• [ ] Added a relevant changelog entry to the Unreleased section in CHANGELOG.md

• [ ] Reviewed Files changed in the github PR explorer

---

For Admin Use:

• Added appropriate labels to PR (ex. wip, ready-for-review, docs)
• Reviewers Assigned
• Squashed all commits, uses message "Merge PR #XYZ: [title]" (coding standards)

[codecov-commenter]

Codecov Report

Merging #3119 (4bb729c) into dev (528b9aa) will decrease coverage by 0.01%. The diff coverage is 100.00%.

:exclamation: Current head 4bb729c differs from pull request most recent head 4f065a9. Consider uploading reports for the commit 4f065a9 to get more accurate results

:mega: This organization is not using Codecov’s GitHub App Integration. We recommend you install it so Codecov can continue to function properly for your repositories. Learn more

@@            Coverage Diff             @@
##              dev    #3119      +/-   ##
==========================================
- Coverage   35.83%   35.83%   -0.01%     
==========================================
  Files         437      437              
  Lines       46064    46065       +1     
==========================================
- Hits        16509    16508       -1     
- Misses      28348    28349       +1     
- Partials     1207     1208       +1     

Impacted Files	Coverage Δ
x/staking/keeper/weight.go	85.71% <100.00%> (+1.09%)	:arrow_up:

... and 1 file with indirect coverage changes