Fix 0pdd issue with "too many leading spaces"

Reading .rubocop.yml...
Reading todo.yml...
ERROR: todo.yml; puzzle at line #16; Too many leading spaces at 24:2; make sure all lines that include the puzzle body start at position #3.
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Exit code is 1

/app/objects/git_repo.rb:66:in `rescue in block in xml'
/app/objects/git_repo.rb:63:in `block in xml'
/app/vendor/ruby-2.6.0/lib/ruby/2.6.0/tempfile.rb:295:in `open'
/app/objects/git_repo.rb:62:in `xml'
/app/objects/puzzles.rb:36:in `deploy'
/app/objects/job.rb:38:in `proceed'
/app/objects/job_starred.rb:33:in `proceed'
/app/objects/job_recorded.rb:32:in `proceed'
/app/objects/job_emailed.rb:35:in `proceed'
/app/objects/job_commiterrors.rb:36:in `proceed'
/app/objects/job_detached.rb:48:in `exclusive'
/app/objects/job_detached.rb:36:in `block in proceed'
/app/objects/job_detached.rb:36:in `fork'
/app/objects/job_detached.rb:36:in `proceed'
/app/0pdd.rb:358:in `block in '

Author: dgroup

test/vcs4sql/sqlite/migration_test.rb

@@ -19,7 +19,6 @@
 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
-#
 
 require_relative "../../sqlite_test"
 require_relative "../../../lib/vcs4sql/sqlite/migration"

todo.yml

@@ -21,14 +21,14 @@
 #  |- lib
 #  |- test
 #  |- upgrade
-#     |- sqlite
-#         |- 00-define-initial-structure.sql
-#         |- 02-add-missing-foreign-keys.sql
-#         |- 03-add-missing-indexes.sql
-#         |- 99-add.testdata.sql
-#     |- postgres
-#         |- ...
-#     |- mysql
-#         |- ...
+#  ||||- sqlite
+#  ||||||||- 00-define-initial-structure.sql
+#  ||||||||- 02-add-missing-foreign-keys.sql
+#  ||||||||- 03-add-missing-indexes.sql
+#  ||||||||- 99-add.testdata.sql
+#  ||||- postgres
+#  ||||||||- ...
+#  |||||- mysql
+#  ||||||||- ...
 #  |- Gemfile
-#  ...
+#  ...