[git] readFullDetailsForHashes should do nothing if empty list of hashes is received

If we don't do this check, git provide full history, or error if repository has no commits

plugins/git4idea/src/git4idea/history/GitLogUtil.java

@@ -373,6 +373,7 @@ public class GitLogUtil {
                                               boolean withFullMergeDiff,
                                               boolean preserveOrder,
                                               @NotNull DiffRenameLimit renameLimit) throws VcsException {
+    if (hashes.isEmpty()) return;
     GitLineHandler handler = createGitHandler(project, root, createConfigParameters(includeRootChanges, renameLimit), lowPriorityProcess);
     sendHashesToStdin(vcs, hashes, handler);