[1.7.x] Fixed #23987 -- Made SQLite SchemaEditor always use effective_default().

Backport of 089047331d972c0ee58d13476fc54f2118bf1359 from master
[1.7.x] Fixed typos in docs/releases/1.7.2.txt.

Backport of d39461eb46b2d11051940e16818baf2f0e1b894d from master
[1.7.x] Fixed #23405 -- Fixed makemigrations prompt when adding Text/CharField.

A default is no longer required.

Backport of d8f3b86a7691c8aa0ec8f5a064ad4c3218250fed from master
[1.7.x] Fixed refs #23987 test on Oracle.

Backport of ac5f2a4ef7b9993502ebc02f487cbb06bfb9bf0a from master