Modify usage of LDAP ping API on UI

[AllForNothing]

Fixes: #14389
Signed-off-by: AllForNothing sshijun@vmware.com

[codecov]

Codecov Report

Merging #14440 (adf9e16) into master (68d7c91) will decrease coverage by 0.01%.
The diff coverage is 20.00%.

@@            Coverage Diff             @@
##           master   #14440      +/-   ##
==========================================
- Coverage   64.62%   64.61%   -0.02%     
==========================================
  Files         919      919              
  Lines       65133    65135       +2     
  Branches     2032     2034       +2     
==========================================
- Hits        42091    42085       -6     
- Misses      19080    19084       +4     
- Partials     3962     3966       +4     

Flag	Coverage Δ
unittests	64.61% <20.00%> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...left-side-nav/config/auth/config-auth.component.ts	58.41% <20.00%> (-2.20%)	⬇️
...ortal/src/app/shared/pipes/harbor-datetime.pipe.ts	60.00% <0.00%> (-40.00%)	⬇️
src/lib/cache/util.go	73.68% <0.00%> (-15.79%)	⬇️

[jwangyangls]

lgtm