[Multi-Database Support][h2] Support run on h2

[hezhangjian]

What's the purpose of this PR

Added support for h2 init sql to ApolloConfig. Verified the following functionalities: adding/disabling/enabling users, adding/deleting namespaces, publishing configurations, and adding applications.

Brief changelog

Add h2 init sql, only effective when h2

How to use it

apollo-config run args

-Dapollo_profile=github,database-discovery
-Dspring.profiles.group.github=h2
-Dspring.datasource.url=jdbc:h2:mem:testdb;mode=mysql;DATABASE_TO_UPPER=FALSE;BUILTIN_ALIAS_OVERRIDE=TRUE;
-Dspring.datasource.username=sa
-Dspring.datasource.password=

apollo-portal run args

-Dapollo_profile=github,auth
-Dspring.profiles.group.github=h2
-Dspring.datasource.url=jdbc:h2:mem:testdb;mode=mysql;DATABASE_TO_UPPER=FALSE;BUILTIN_ALIAS_OVERRIDE=TRUE;
-Dspring.datasource.username=sa
-Dspring.datasource.password=
-Ddev_meta=http://localhost:8080/

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.

[nobodyiam]

Hello, I am a serverless review bot on flows.network. Here are my reviews of code commits in this PR.

---

Commit 1

This patch adds support for the h2 database to Apollo. It does this by adding an h2 initialization script, an annotation for running the script and a datasource field. The h2 initialization script makes changes to the ServerConfig table by adding a new row. There are no apparent potential problems with this patch.

[nobodyiam]

review again

[nobodyiam]

Hello, I am a code review bot on flows.network. Here are my reviews of code commits in this PR.

---

[codecov]

Codecov Report

Merging #4851 (e05aaa4) into master (a4df1a3) will increase coverage by 0.09%.
The diff coverage is 42.85%.

@@             Coverage Diff              @@
##             master    #4851      +/-   ##
============================================
+ Coverage     48.36%   48.46%   +0.09%     
- Complexity     1722     1725       +3     
============================================
  Files           346      346              
  Lines         10827    10835       +8     
  Branches       1078     1080       +2     
============================================
+ Hits           5237     5251      +14     
+ Misses         5268     5260       -8     
- Partials        322      324       +2     

Impacted Files	Coverage Δ
...mework/apollo/biz/service/BizDBPropertySource.java	80.00% <42.85%> (-0.56%)	⬇️
.../apollo/portal/service/PortalDBPropertySource.java	39.13% <42.85%> (+7.55%)	⬆️

... and 4 files with indirect coverage changes

[nobodyiam]

LGTM