fix: Pass index type for Scalar indexes

[congqixia]

Related to #694 #695

[congqixia]

/kind bug

[sre-ci-robot]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.93%. Comparing base (7d66951) to head (940e853).
Report is 2 commits behind head on master.

❗ Current head 940e853 differs from pull request most recent head 270cde5. Consider uploading reports for the commit 270cde5 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #696      +/-   ##
==========================================
+ Coverage   71.90%   71.93%   +0.03%     
==========================================
  Files          51       51              
  Lines        4751     4754       +3     
==========================================
+ Hits         3416     3420       +4     
+ Misses       1211     1210       -1     
  Partials      124      124              

Files	Coverage Δ
entity/index_scalar.go	100.00% <100.00%> (+14.28%)	⬆️

[ThreadDao]

/lgtm