fix(server): add tip for gremlin api NPE with empty query by SunnyBoy-WYH · Pull Request #2467 · apache/hugegraph

@@             Coverage Diff              @@
##             master    #2467      +/-   ##
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+ Coverage     63.80%   64.84%   +1.04%     
- Complexity      829      980     +151     
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  Files           511      511              
  Lines         42622    42623       +1     
  Branches       5947     5947              
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+ Hits          27193    27637     +444     
+ Misses        12679    12245     -434     
+ Partials       2750     2741       -9