[doc] Add deprecation of 'cosmetic_changes-append' to ROADMAP.rst

'cosmetic_changes-append' were restored but the are still deprecated;
But Pywikibot 7 still needs these messages due to a twtranslation()
bug.

Bug: T326470
Change-Id: Idbe860d64dcaebb6fc367992c5467c78cc6f6224
---
M ROADMAP.rst
1 file changed, 15 insertions(+), 0 deletions(-)

diff --git a/ROADMAP.rst b/ROADMAP.rst
index 59ae273..e184105 100644
--- a/ROADMAP.rst
+++ b/ROADMAP.rst
@@ -119,6 +119,7 @@
 * 7.0.0: A boolean watch parameter in Page.save() is deprecated and will be desupported
 * 7.0.0: baserevid parameter of editSource(), editQualifier(), removeClaims(), removeSources(), remove_qualifiers() DataSite methods will be removed
 * 7.0.0: Values of APISite.allpages() parameter filterredir other than True, False and None are deprecated
+* 7.0.0: The i18n identifier 'cosmetic_changes-append' will be removed in favour of 'pywikibot-cosmetic-changes'
 * 6.5.0: OutputOption.output() method will be removed in favour of OutputOption.out property
 * 6.5.0: Infinite rotating file handler with logfilecount of -1 is deprecated
 * 6.4.0: 'allow_duplicates' parameter of :func:`tools.itertools.intersect_generators` as positional argument is deprecated, use keyword argument instead

