Update Media and File namespace names for Swahili

The "File" namespace was defined as "Picha", which means "Image",
and the "File talk" namespace was defined as "Majadiliano_ya_faili",
which actually means "File talk".

The "Media" namespace was defined as "Faili", which means "File".
The definitions of "Media" and "File" are obviously a mistake.

"Faili:" was used on eight pages in the Swahili Wikipedia
and on one page in the Swahili Wiktionary. In all of them
it was used incorrectly, and I corrected them all. Now it doesn't
appear on any pages in any Wikimedia project.

The "Media" namespace can have the same name as in English,
so that line is removed here. File now actually becomes "Faili".

Bug: T304920
Change-Id: I742798459a6b3f2141bccf180d342f1c2055a932

RELEASE-NOTES-1.39

@@ -87,6 +87,11 @@ MediaWiki supports over 350 languages. Many localisations are updated regularly.
 Below only new and removed languages are listed, as well as changes to languages
 because of Phabricator reports.
 
+* (T304920) In Swahili, The "Media" namespace is now "Media", as in English,
+  and the "File" namespace is now "Faili". The old name of the "File" namespace
+  was "Picha", and it's kept for backwards compatibility. If you manage a wiki
+  in Swahili, and you use "Faili:" as a namespace anywhere in wikitext, and
+  you mean to use it as "Media:", these need to be replaced to "Media:".
 * …
 
 === Breaking changes in 1.39 ===
@@ -123,6 +128,8 @@ because of Phabricator reports.
 * Changes to ResourceLoader modules:
   - The mediawiki.viewport module, deprecated in 1.37 has been
      removed. Use IntersectionObserver instead.
+* If you manage a wiki in Swahili, and you use "Faili:" as a namespace anywhere,
+  and you mean to use it as "Media:", replace it with "Media:". See T304920.
 * Changes to skins:
   - Skin::getCopyrightIcon(), ::getPoweredBy(), deprecated in 1.37 have been
     removed.

languages/messages/MessagesSw.php

@@ -20,13 +20,12 @@
  */
 
 $namespaceNames = [
-	NS_MEDIA            => 'Faili',
 	NS_SPECIAL          => 'Maalum',
 	NS_TALK             => 'Majadiliano',
 	NS_USER             => 'Mtumiaji',
 	NS_USER_TALK        => 'Majadiliano_ya_mtumiaji',
 	NS_PROJECT_TALK     => 'Majadiliano_ya_$1',
-	NS_FILE             => 'Picha',
+	NS_FILE             => 'Faili',
 	NS_FILE_TALK        => 'Majadiliano_ya_faili',
 	NS_MEDIAWIKI_TALK   => 'Majadiliano_ya_MediaWiki',
 	NS_TEMPLATE         => 'Kigezo',
@@ -38,6 +37,7 @@ $namespaceNames = [
 ];
 
 $namespaceAliases = [
+	'Picha'                 => NS_FILE,
 	'$1_majadiliano'        => NS_PROJECT_TALK,
 	'Majadiliano_faili'     => NS_FILE_TALK,
 	'MediaWiki_majadiliano' => NS_MEDIAWIKI_TALK,