tcl-tk: Fix ttk::ThemeChanged errors

This error is an annoyance particularly for Tkinter users
(see e.g. python/cpython#71383); it will be fixed in Tk 8.6.14.

Formula/tcl-tk.rb

@@ -5,7 +5,7 @@ class TclTk < Formula
   mirror "https://fossies.org/linux/misc/tcl8.6.13-src.tar.gz"
   sha256 "43a1fae7412f61ff11de2cfd05d28cfc3a73762f354a417c62370a54e2caf066"
   license "TCL"
-  revision 2
+  revision 3
 
   livecheck do
     url :stable
@@ -54,6 +54,13 @@ class TclTk < Formula
     url "https://downloads.sourceforge.net/project/tcl/Tcl/8.6.13/tk8.6.13-src.tar.gz"
     mirror "https://fossies.org/linux/misc/tk8.6.13-src.tar.gz"
     sha256 "2e65fa069a23365440a3c56c556b8673b5e32a283800d8d9b257e3f584ce0675"
+
+    # Bugfix for ttk::ThemeChanged errors; will be in Tk 8.6.14
+    # See https://core.tcl-lang.org/tk/info/310c74ecf4
+    patch :p0 do
+      url "https://github.com/raw/macports/macports-ports/db4f8f774193/x11/tk/files/fix-themechanged-error.patch"
+      sha256 "2a75496dc597dec9d25401ab002f290be74d4acd5566793c5114e75a154c280a"
+    end
   end
 
   resource "itk4" do