[EPIC] Good first issues

[qqqttt123]

Describe the proposal

These issues are a great way to get started with a project. Any contribution is important for the Gravitino community. If the issues have been assigned to others, but there isn't any progress for more than 3 months. You can ask maintainers (https://github.com/datastrato/gravitino/blob/main/MAINTAINERS.md) to assign it to you, too.
The steps of contribution is as follows:
https://github.com/datastrato/gravitino/blob/main/CONTRIBUTING.md

Task list

Simple Tasks:

If you're not familiar about the code of Gravitino and want to realize this project by some tasks. These issues are suitable for you.

• [Improvement] add multi PostgreSQL server version to CatalogPostgreSqlIT Integrate test to improve compatibility #1361
• [Improvement] add multi MySQL server version to CatalogMysqlIT Integrate test to improve compatibility #1367
• [Improvement] Check whether a hive table is external when purge table #1390

Code Style Improvements:

If you're not familiar about Gravitino but you have some experience about Java. These issues are suitable for you.

• [Improvement] Remove Lombok annotation from API module #1220
• [Improvement] Files missing headers and license #1267
• [Improvement] Support sequence in the configuration #1357
• [Improvement] add gc related opts when start gravitino server #592

CI and Build Improvements:

If you're not familiar about Gravitino but have some experience about Github Actions or Gradle. These issues are suitable for you.

• [Bug report] The CI cannot be triggered automatically when a backport PR is created by github bot #1282
• [Improvement] After a ./gradlew clean class files still exist #1268
• [Improvement] Setting the workflow depends #768
• [Improvement] Add copyright check for new files #1377

Document Improvements:

If you don't have much experience about Java and Gravitino but want to contribute to this project. You can try to improve the documents of this project.

• [Subtask] Add more badges in README #1346

[jerryshao]

Close as duplicated.