GitPython: Unguarded git read-tree option forwarding in IndexFile.from_tree/reset/merge_tree enables arbitrary file overwrite

SummaryIndexFile.fromtree, IndexFile.reset → fromtree and IndexFile.mergetree append caller-influenced treeish strings positionally to git read-tree with no unsafe-option guard, no allowunsafeoptions parameter, and no -- separator. git read-tree --index-output= writes the resulting index to an...