Set max depth when cloning a git repository

[ikhoon]

To support multiple sub-repositories, which mentioned in #575, we need to copy a snapshot of the existing git repository to a new one with truncating the original histories.
GitRepository already has some APIs that clones a git repository to another directory. However, it can not limit the number of max histories.

centraldogma/server/src/main/java/com/linecorp/centraldogma/server/internal/storage/repository/git/GitRepository.java

Lines 1593 to 1598 in 1ceed8a

	/**
	* Clones this repository into a new one.
	*/
	public void cloneTo(File newRepoDir) {
	cloneTo(newRepoDir, GitRepositoryFormat.V1);
	}

It seems like a good idea to handle this issue first before proceeding with #575.

[minwoox]

Thanks for the good opinion. Let me handle this together with #575. 😄