Merge branch 'ps/leakfixes-part-4' into ps/leakfixes-part-5

* ps/leakfixes-part-4: (22 commits) builtin/diff: free symmetric diff members diff: free state populated via options builtin/log: fix leak when showing converted blob contents userdiff: fix leaking memory for configured diff drivers builtin/format-patch: fix various trivial memory leaks diff: fix leak when parsing invalid ignore regex option unpack-trees: clear index when not propagating it sequencer: release todo list on error paths merge-ort: unconditionally release attributes index builtin/fast-export: plug leaking tag names builtin/fast-export: fix leaking diff options builtin/fast-import: plug trivial memory leaks builtin/notes: fix leaking `struct notes_tree` when merging notes builtin/rebase: fix leaking `commit.gpgsign` value config: fix leaking comment character config submodule-config: fix leaking name entry when traversing submodules read-cache: fix leaking hashfile when writing index fails bulk-checkin: fix leaking state TODO object-name: fix leaking symlink paths in object context object-file: fix memory leak when reading corrupted headers ...