feat(openapi): create app (#32)

[ThugJudy]

• feat(openapi): create app

• feat(openapi): create app

• fix: remove create app by env

• feat: support init admins when create app

• refactor: path "apps/create" -> "apps"

• test: move to IntegrationTest

• Update AppOpenApiServiceTest.java

• refactor: use OpenCreateAppDTO instead of OpenAppDTO

• test: testCreateAppThenCreateNamespaceThenRelease

• Update CHANGES.md

• add assignAppRoleToSelf to mark role permission

• testCreateAppButHaveNoAppRole

• refactor: use composite instead of extend OpenAppDTO

• Update OpenCreateAppDTO.java

• test: make test more complex. create the cluster too

What's the purpose of this PR

Fix the test case com.ctrip.framework.apollo.openapi.client.service.ItemOpenApiServiceTest.testFindItemsByNamespace

Which issue(s) this PR fixes:

Fixes #43

Brief changelog

I propose using a LinkedHashMap, so that the order in which the params are inserted is preserved and flakiness is resolved.
https://github.com/ThugJudy/apollo-java/blob/d8e4352ff8c9e9c6fc37961c49d4b7018b47fc14/apollo-openapi/src/main/java/com/ctrip/framework/apollo/openapi/client/url/OpenApiPathBuilder.java#L64

Follow this checklist to help us incorporate your contribution quickly and easily:

• Read the Contributing Guide before making this pull request.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Write necessary unit tests to verify the code.
• Run mvn clean test to make sure this pull request doesn't break anything.
• Update the CHANGES log.

[codecov]

Codecov Report

Merging #44 (d8e4352) into main (5344bc4) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##               main      #44   +/-   ##
=========================================
  Coverage     68.59%   68.59%           
  Complexity     1206     1206           
=========================================
  Files           171      171           
  Lines          5196     5196           
  Branches        561      561           
=========================================
  Hits           3564     3564           
  Misses         1371     1371           
  Partials        261      261           

Files	Coverage Δ
.../apollo/openapi/client/url/OpenApiPathBuilder.java	96.49% <100.00%> (ø)

[nobodyiam]

LGTM