[1.7.x] Fixed #23072 -- Added missing formtools test templates in tarball

The lack of this file breaks the test suite.
Backport of a2d0831e42 from master.
[1.7.x] Fixed typo in docs/ref/contrib/admin/index.txt.

Backport of 06ba4b9eee from master
[1.7.x] Added warning in tutorial 4 that the regex capture group name has changed.

Backport of 731f313d60 from master