pythongh-96954: Don't run regen-unicodedata in regen-all (python#112120)

The "make regen-unicodedata" should now be run manually. By the
default, it requires an Internet connection, which is not always the
case. Some Linux distributions build Linux packages in isolated
environment (without network).

Makefile.pre.in

@@ -1359,10 +1359,10 @@ regen-unicodedata:
 regen-all: regen-cases regen-typeslots \
 	regen-token regen-ast regen-keyword regen-sre regen-frozen \
 	regen-pegen-metaparser regen-pegen regen-test-frozenmain \
-	regen-test-levenshtein regen-global-objects regen-unicodedata
+	regen-test-levenshtein regen-global-objects
 	@echo
-	@echo "Note: make regen-stdlib-module-names, make regen-limited-abi"
-	@echo "and make regen-configure should be run manually"
+	@echo "Note: make regen-stdlib-module-names, make regen-limited-abi, "
+	@echo "make regen-configure and make regen-unicodedata should be run manually"
 
 ############################################################################
 # Special rules for object files