Suggest to make unitycatalog to be a pure Java repository

Currently, the unitycatalog is mixed by Java and Scala code, while 90% of the code is Java code. I can only see 3 files are Scala code.

find . -type f -name '*.scala' 
./connectors/spark/src/main/scala/io/unitycatalog/spark/UCSingleCatalog.scala
./project/Tarball.scala
./project/PythonClientPostBuild.scala
./project/ReleaseSettings.scala

Personally, I will suggest to turn the unitycatalog to be a pure java repository, which will make us easier to manage the whole dev loop. For example, all of the following dev loop can focus only on Java

• Codestyle enforcement
• Github CI testing
• Test framework and abstraction.

Also if we finally turn to pure java repo, then we also don't need to be distract for different Scala compatible issues.

Start by reviewing the Scala files listed in the issue: connectors/spark/src/main/scala/io/unitycatalog/spark/UCSingleCatalog.scala and the project/*.scala files. Then inspect the repository’s CI, codestyle, test, and build configuration to determine the scope of removing Scala. Done means the repository’s Java-only direction and any required handling of these files are agreed and implemented.