### Motivation:
Make E2E tests more stable.
### Modifications:
Verify the traces loosely as other tests, and remove the `verify` method which verifies traces strictly, as we have preparation that also generates traces.
### Result:
E2E tests are more stable.
* Update JDK compiling level to 8, and remove zip dist.
* Exclude annotation and shade API.
* Fix more exclusion.
* 1. Update grava and gson 2. Fix compile issue. 3. Keep protoc and maven plugin in old version. Some incompatible of 3rd party grpc proto.
* Fix dependency conflicts, license and notice issue, and dependency check script issue
Co-authored-by: kezhenxu94 <kezhenxu94@163.com>
* [Feature] Officially support ElasticSearch 7 as backend storage
* Extract bootstrap module to be shared by multiple starters
* Add missing configuration file and distinguish different version in test
* Update known-oap-backend-dependencies-es7.txt
Update the dependency lib
* Fix missing adaptation to ElasticSearch 7
* Rename ElasticSearch 7 specific class with Es7 infix
* Fix miss-adapted ElasticSearch DAO API
* Add ES7 specific configuration and polish documentations
* Polish documentations
* Polish documentations
Jared Tan
Daming
kezhenxu94
吴晟 Wu Sheng