Pull request: all: rework file perms

Updates #3198.

Squashed commit of the following:

commit 3de1ecf4535220cdd769100ef0ea96c166419d12
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Fri May 28 18:39:52 2021 +0300

    all: imp chlog

commit f1a46efed917c9b70f047505449a816284d7c71e
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Fri May 28 18:13:55 2021 +0300

    all: rework file perms

CHANGELOG.md

@@ -21,6 +21,10 @@ and this project adheres to
 - New flag `--local-frontend` to serve dinamically changeable frontend files
   from disk as opposed to the ones that were compiled into the binary.
 
+### Changed
+
+- Permissions on filter files are now `0o644` instead of `0o600` ([#3198]).
+
 ### Deprecated
 
 <!--
@@ -43,6 +47,7 @@ released by then.
 [#3184]: https://github.com/AdguardTeam/AdGuardHome/issues/3184
 [#3185]: https://github.com/AdguardTeam/AdGuardHome/issues/3185
 [#3186]: https://github.com/AdguardTeam/AdGuardHome/issues/3186
+[#3198]: https://github.com/AdguardTeam/AdGuardHome/issues/3198