merge(third_party/git): Merge squashed git subtree at v2.23.0

Merge commit '1b593e1ea4' as 'third_party/git'

third_party/git/Documentation/RelNotes/1.7.10.4.txt

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+Git v1.7.10.4 Release Notes
+===========================
+
+Fixes since v1.7.10.3
+---------------------
+
+ * The message file for Swedish translation has been updated a bit.
+
+ * A name taken from mailmap was copied into an internal buffer
+   incorrectly and could overun the buffer if it is too long.
+
+ * A malformed commit object that has a header line chomped in the
+   middle could kill git with a NULL pointer dereference.
+
+ * An author/committer name that is a single character was mishandled
+   as an invalid name by mistake.
+
+ * The progress indicator for a large "git checkout" was sent to
+   stderr even if it is not a terminal.
+
+ * "git grep -e '$pattern'", unlike the case where the patterns are
+   read from a file, did not treat individual lines in the given
+   pattern argument as separate regular expressions as it should.
+
+ * When "git rebase" was given a bad commit to replay the history on,
+   its error message did not correctly give the command line argument
+   it had trouble parsing.
+
+Also contains minor fixes and documentation updates.