add close for connect provider & refactor ssl name

[Nicole00]

No description provided.

[codecov-commenter]

Codecov Report

Merging #31 (5ef85a0) into master (c8d25d6) will decrease coverage by 0.59%.
The diff coverage is 51.85%.

@@             Coverage Diff              @@
##             master      #31      +/-   ##
============================================
- Coverage     40.43%   39.83%   -0.60%     
  Complexity      142      142              
============================================
  Files            46       46              
  Lines          1365     1373       +8     
  Branches        124      128       +4     
============================================
- Hits            552      547       -5     
- Misses          765      776      +11     
- Partials         48       50       +2     

Impacted Files	Coverage Δ
...connector/nebula/sink/NebulaBatchOutputFormat.java	45.16% <0.00%> (-3.97%)	⬇️
...bula/connection/NebulaGraphConnectionProvider.java	71.42% <50.00%> (-5.50%)	⬇️
...nnector/nebula/connection/NebulaClientOptions.java	81.08% <75.00%> (-7.97%)	⬇️
...ache.flink/connector/nebula/utils/SSLSighType.java	100.00% <100.00%> (ø)

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