fix: make field key matching in x/token & x/collection case-sensitive

[0Tech]

Description

This patch would make the field key matching in x/token & x/collection case-sensitive.

Checklist:

• I followed the contributing guidelines and code of conduct.
• I have added a relevant changelog to CHANGELOG.md
• I have added tests to cover my changes.
• I have updated the documentation accordingly.
• I have updated API documentation client/docs/swagger-ui/swagger.yaml

[codecov]

Codecov Report

Merging #784 (ea514b3) into rc9/v0.46.0 (6792efe) will decrease coverage by 0.00%.
The diff coverage is 77.77%.

❗ Current head ea514b3 differs from pull request most recent head 78da306. Consider uploading reports for the commit 78da306 to get more accurate results

Additional details and impacted files

@@               Coverage Diff               @@
##           rc9/v0.46.0     #784      +/-   ##
===============================================
- Coverage        62.15%   62.15%   -0.01%     
===============================================
  Files              877      880       +3     
  Lines            99419    99492      +73     
===============================================
+ Hits             61796    61838      +42     
- Misses           34019    34031      +12     
- Partials          3604     3623      +19     

Impacted Files	Coverage Δ
x/collection/collection.go	80.35% <ø> (ø)
x/collection/keeper/keys.go	100.00% <ø> (ø)
x/token/validation.go	72.72% <0.00%> (-12.73%)	⬇️
x/collection/msgs.go	51.33% <66.66%> (+3.42%)	⬆️
x/collection/keeper/supply.go	89.20% <100.00%> (+0.08%)	⬆️
x/token/keeper/supply.go	91.07% <100.00%> (+0.03%)	⬆️
crypto/keys/internal/ecdsa/privkey.go	82.45% <0.00%> (-1.76%)	⬇️
x/token/msgs.go	48.28% <0.00%> (-1.15%)	⬇️
x/auth/types/keys.go	100.00% <0.00%> (ø)
... and 6 more

[0Tech]

CI fails due to the latest changes of workflow in rc9/v0.46.0.