Merge branch 'js/fast-export-paths-with-spaces' into maint

"git fast-export" produced an input stream for fast-import without
properly quoting pathnames when they contain SPs in them.

* js/fast-export-paths-with-spaces:
  fast-export: quote paths with spaces

t/t9350-fast-export.sh

@@ -430,7 +430,7 @@ test_expect_success 'fast-export quotes pathnames' '
 	 git commit -m rename &&
 	 git read-tree --empty &&
 	 git commit -m deletion &&
-	 git fast-export HEAD >export.out &&
+	 git fast-export -M HEAD >export.out &&
 	 git rev-list HEAD >expect &&
 	 git init result &&
 	 cd result &&