t/t5538-push-shallow.sh: use the $( ... ) construct for command substitution

diff --git a/t/t3100-ls-tree-restrict.sh b/t/t3100-ls-tree-restrict.sh
index eb73c06a4e1ee826684ee84efa134ee5517023a6..325114f8fee810ac9cf1836f50e060f69b5fe46e 100755 (executable)
--- a/t/t3100-ls-tree-restrict.sh
+++ b/t/t3100-ls-tree-restrict.sh
@@ -28,7 +28,7 @@ test_expect_success \
      echo Mi >path2/baz/b &&
      find path? \( -type f -o -type l \) -print |
      xargs git update-index --add &&
-     tree=`git write-tree` &&
+     tree=$(git write-tree) &&
      echo $tree'
 
 test_output () {