Tools: Handle Proposed the same as Experimental for GitHub tags

Previously changes to Proposed status asked for Council approval, when it should only require author approval.
As Proposed is basically Experimental, just after Last Call was started, it is the task of the author to incorporate feedback with no further involvement of Council needed.

tools/github_auto_triage_pr.sh

@@ -103,9 +103,9 @@ do
 
     status="$(xpath "$xep" '/xep/header/status/text()')"
     approvers=""
-    if echo "$status" | grep -E '^(Experimental|Deferred)$' &>/dev/null
+    if echo "$status" | grep -E '^(Experimental|Proposed|Deferred)$' &>/dev/null
     then
-        # Experimental or Deferred
+        # Experimental, Proposed or Deferred
         if [ "$status" == 'Deferred' ]
         then
             add_tag "Needs Editor Action"
@@ -115,7 +115,7 @@ do
 
         approvers="$(xpath "$xep" '/xep/header/author/email/text()' | sort -u)"
     else
-        # *not* Experimental or Deferred
+        # *not* Experimental, Proposed or Deferred
         approvers="$(xpath "$xep" '/xep/header/approver/text()' 2>/dev/null || echo 'Unknown')"
     fi