Documentation policy change suggestion

Dear Docutils developers,

I suggest the following change to the "Docutils Project Policies":

diff --git a/docutils/docs/dev/policies.txt b/docutils/docs/dev/policies.txt
index f46c143d2..6be340155 100644
--- a/docutils/docs/dev/policies.txt
+++ b/docutils/docs/dev/policies.txt
@@ -110,8 +110,7 @@ Documentation Conventions
 
 * Docutils documentation is written using reStructuredText, of course.
 
-* Use 7-bit ASCII if at all possible, and Unicode substitutions when
-  necessary.
+* The encoding of the documentation files is UTF-8. 
 
 * Use the following section title adornment styles::
 

Rationale:

Adapt the Policies to the state of the art in 2022:

* Unicode and UTF-8 are now mainstream, no longer an obstacle to
  easy viewing and editing of the source files.
  
* Unicode substitutions, while 7-bit ASCII save, are harder to read and
  understand than literal Unicode characters.
  
  The use of substitutions for "exotic" characters that are hard to reach at
  the keyboard or missing in many fixed-width fonts is up to the discretion
  of the individual authors/editors.
  
.. include:: <isolat1.txt>
  
G|uuml|nter