move zkRegCenter.init() and zkRegCenter.close() to @BeforeAll and @AfterAll to make tests run faster and look similar to other tests

[TestBoost]

Changes proposed in this pull request:

• put zkRegCenter.init(); and zkRegCenter.close(); into the method body of @BeforeAll and @AfterAll. There are three tests in the test class OneOffJobBootstrapTest. However, these three tests are justing trying to use zkRegCenter to initialize some objects and they are not modifying zkRegCenter.
• Besides, we searched for all the tests which contain zkRegCenter.init(); and zkRegCenter.close();. All tests in the project apache/shardingsphere-elasticjob except OneOffJobBootstrapTest put zkRegCenter.init(); and zkRegCenter.close(); into the method body of @BeforeAll and @AfterAll.
• The test runtime can jump from 3.489 s to 2.403 s after applying the changes when run on our machine.

[TestBoost]

Sorry for the checkstyle issues. I tried to run with ./mvnw spotless:apply -Pcheck -T1C and ./mvnw checkstyle:check -Pcheck -T1C, but it all passes. But when I checked the log, I found there is a tab in the changed test class file. I just changed it to whitespace and do not know if it works now.

[codecov-commenter]

Codecov Report

Attention: 13 lines in your changes are missing coverage. Please review.

Comparison is base (a8ba448) 80.10% compared to head (98bf060) 79.61%. Report is 23 commits behind head on master.

Files	Patch %	Lines
.../rdb/storage/repository/RDBJobEventRepository.java	91.04%	3 Missing and 3 partials :warning:
.../tracing/rdb/storage/sql/SQLPropertiesFactory.java	71.42%	1 Missing and 1 partial :warning:
...here/elasticjob/http/executor/HttpJobExecutor.java	95.45%	0 Missing and 1 partial :warning:
...ing/rdb/config/RDBTracingStorageConfiguration.java	66.66%	0 Missing and 1 partial :warning:
...e/type/impl/DefaultTracingStorageDatabaseType.java	0.00%	1 Missing :warning:
.../tracing/rdb/yaml/YamlDataSourceConfiguration.java	0.00%	1 Missing :warning:
...rdb/yaml/YamlDataSourceConfigurationConverter.java	50.00%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #2378 +/- ## ============================================ - Coverage 80.10% 79.61% -0.50% + Complexity 1113 1106 -7 ============================================ Files 204 204 Lines 3821 3806 -15 Branches 445 443 -2 ============================================ - Hits 3061 3030 -31 - Misses 570 585 +15 - Partials 190 191 +1 ```

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