Update CHANGELOG to describe configuration files location changes (#3990)

* Update CHANGELOG to describe configuration files location changes

motivation: document user visible changes in change log

changes: Update CHANGELOG to include configuration files location changes

Co-authored-by: Anders Bertelrud <[email protected]>

Author: tomerd

CHANGELOG.md

@@ -25,17 +25,24 @@ Swift 5.6
 * [#3641]
 
   Adding a dependency requirement can now be done with the convenience initializer `.package(url: String, exact: Version)`.
-  
-* [#3890]
-
-  To increase the security of packages, SwiftPM performs trust on first use (TOFU) validation. The fingerprint of a package is now being recorded when the package is first downloaded from a Git repository or package registry. Subsequent downloads must have fingerpints matching previous recorded values, otherwise it would result in build warnings or failures depending on settings.   
 
 * [#3641]
 
   Dependency requirement enum calling convention is deprecated in favour of labeled argument:    
     * `.package(url: String, .branch(String))` -> `.package(url: String, branch: String)`
     * `.package(url: String, .revision(String))` -> `.package(url: String, revision: String)`    
-    * `.package(url: String, .exact(Version))` -> `.package(url: String, exact: Version)`    
+    * `.package(url: String, .exact(Version))` -> `.package(url: String, exact: Version)` 
+
+* [#3890]
+
+  To increase the security of packages, SwiftPM performs trust on first use (TOFU) validation. The fingerprint of a package is now being recorded when the package is first downloaded from a Git repository or package registry. Subsequent downloads must have fingerpints matching previous recorded values, otherwise it would result in build warnings or failures depending on settings.   
+
+* [#3670], [#3901], [#3942]
+  
+  Location of configuration files (including mirror file) have changed to accomodate new features that require more robust configuration directories structure, such as SE-0292:
+  
+  * `<project>/.swiftpm/config` (mirrors file) was moved to `<project>/.swiftpm/configuration/mirrors.json`. SwiftPM 5.6 will automatically copy the file from the old location to the new one and emit a warning to prompt the user to delete the file from the old location.
+  * `~/.swiftpm/config/collections.json` (collections file) was moved to `~/.swiftpm/configuration/collections.json`. SwiftPM 5.6 will automatically copy the file from the old location to the new one and emit a warning to prompt the user to delete the file from the old location.
 
 Swift 5.5
 -----------
@@ -191,4 +198,7 @@ Swift 3.0
 [#3486]: https://github.com/apple/swift-package-manager/pull/3486
 [#3641]: https://github.com/apple/swift-package-manager/pull/3641
 [#3649]: https://github.com/apple/swift-package-manager/pull/3649
+[#3670]: https://github.com/apple/swift-package-manager/pull/3670
 [#3890]: https://github.com/apple/swift-package-manager/pull/3890
+[#3901]: https://github.com/apple/swift-package-manager/pull/3901
+[#3942]: https://github.com/apple/swift-package-manager/pull/3942