recovered bundle icons (not application) from macos_app;

Binary file lib/logo/isabelle.icns has changed

--- a/src/Pure/Admin/build_release.scala	Tue Jan 05 22:28:33 2021 +0100
+++ b/src/Pure/Admin/build_release.scala	Tue Jan 05 22:40:58 2021 +0100
@@ -305,6 +305,8 @@
 <dict>
 <key>CFBundleDevelopmentRegion</key>
 <string>English</string>
+<key>CFBundleIconFile</key>
+<string>isabelle.icns</string>
 <key>CFBundleIdentifier</key>
 <string>de.tum.in.isabelle.""" + isabelle_name + """</string>
 <key>CFBundleDisplayName</key>
@@ -646,9 +648,10 @@
             val isabelle_app = Path.explode(isabelle_name + ".app")
             val app_dir = tmp_dir + isabelle_app
             val app_contents = app_dir + Path.explode("Contents")
+            val app_resources =
+              Isabelle_System.make_directory(app_contents + Path.explode("Resources"))
 
-            File.move(tmp_dir + Path.explode(isabelle_name),
-              Isabelle_System.make_directory(app_contents + Path.explode("Resources")))
+            File.move(tmp_dir + Path.explode(isabelle_name), app_resources)
 
             val isabelle_home = Path.explode("Contents/Resources/" + isabelle_name)
             val isabelle_options = Path.explode("Isabelle.options")
@@ -658,6 +661,9 @@
             File.link(
               isabelle_home + isabelle_options, app_dir + isabelle_options, force = true)
 
+            File.copy(
+              app_dir + isabelle_home + Path.explode("lib/logo/isabelle.icns"), app_resources)
+
             make_isabelle_app(
               app_dir + Path.explode(isabelle_name),
               isabelle_home.implode, jdk_component, classpath)