message: Fix a typo in an example in lite/string_util.
diff: @@ -22,7 +22,7 @@ limitations under the License.
  // Example of a string tensor:
  // [
  // 2, 0, 0, 0, # 2 strings.
  -// 16, 0, 0, 0, # 0-th string starts from index 12.
  +// 16, 0, 0, 0, # 0-th string starts from index 16.
  // 18, 0, 0, 0, # 1-st string starts from index 18.
  // 18, 0, 0, 0, # total length of array.
  // 'A', 'B', # 0-th string [16..17]: "AB"
  