avoid crash of JLine on Windows;

--- a/lib/Tools/scala	Fri Sep 16 15:45:40 2022 +0200
+++ b/lib/Tools/scala	Fri Sep 16 16:02:28 2022 +0200
@@ -12,4 +12,8 @@
 export jvm_cp_args="$(platform_path "$ISABELLE_CLASSPATH")"
 export JAVA_OPTS="$ISABELLE_JAVA_SYSTEM_OPTIONS -J-Dscala.usejavacp=true"
 
+if [ "$ISABELLE_PLATFORM_FAMILY" = "windows" ]; then
+  export TERM=dumb
+fi
+
 isabelle_scala scala $ISABELLE_SCALAC_OPTIONS "$@"