docs: announce venv creation before installing packages (#117036)

diff --git a/Doc/Makefile b/Doc/Makefile
index 38fd60f..dd068c5 100644
--- a/Doc/Makefile
+++ b/Doc/Makefile
@@ -163,6 +163,7 @@
 		echo "venv already exists."; \
 		echo "To recreate it, remove it first with \`make clean-venv'."; \
 	else \
+		echo "Creating venv in $(VENVDIR)"; \
 		$(PYTHON) -m venv $(VENVDIR); \
 		$(VENVDIR)/bin/python3 -m pip install --upgrade pip; \
 		$(VENVDIR)/bin/python3 -m pip install -r $(REQUIREMENTS); \