[Fix] Fix typo and link

[Junjun2016]

Fix typo and link.

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[codecov]

Codecov Report

Merging #608 (c5a4648) into master (8f8abe3) will not change coverage.
The diff coverage is n/a.

❗ Current head c5a4648 differs from pull request most recent head 6fe7b08. Consider uploading reports for the commit 6fe7b08 to get more accurate results

@@           Coverage Diff           @@
##           master     #608   +/-   ##
=======================================
  Coverage   85.45%   85.45%           
=======================================
  Files         101      101           
  Lines        5220     5220           
  Branches      840      840           
=======================================
  Hits         4461     4461           
  Misses        586      586           
  Partials      173      173           

Flag	Coverage Δ
unittests	85.45% <ø> (ø)

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[clownrat6]

It's ok to merge.