[1.7.x] Made minor typographic correction to SECRET_KEY docs.
[1.7.x] Made minor typographic correction to SECRET_KEY docs.

Backport of 2bb00b0b0b5232aff806c8a9b3f1126c1cf79221 from master.

oscaro/django,oscaro/django,oscaro/django,jyotsna1820/django,oscaro/django,jyotsna1820/django,jyotsna1820/django,jyotsna1820/django