[PR #10366/3fb2c8df backport][3.12] Fix sdist make (#10368)

**This is a backport of PR #10366 as merged into master
(3fb2c8d).**

Co-authored-by: Michał Górny <[email protected]>

Author: patchback[bot]

Diff for: CHANGES/10366.packaging

@@ -0,0 +1,2 @@
+Added missing files to the source distribution to fix ``Makefile`` targets.
+Added a ``cythonize-nodeps`` target to run Cython without invoking pip to install dependencies.

Diff for: MANIFEST.in

@@ -7,6 +7,7 @@ graft aiohttp
 graft docs
 graft examples
 graft tests
+graft tools
 graft requirements
 recursive-include vendor *
 global-include aiohttp *.pyi

Diff for: Makefile

@@ -81,6 +81,9 @@ generate-llhttp: .llhttp-gen
 .PHONY: cythonize
 cythonize: .install-cython $(PYXS:.pyx=.c) aiohttp/_websocket/reader_c.c
 
+.PHONY: cythonize-nodeps
+cythonize-nodeps: $(PYXS:.pyx=.c) aiohttp/_websocket/reader_c.c
+
 .install-deps: .install-cython $(PYXS:.pyx=.c) aiohttp/_websocket/reader_c.c $(call to-hash,$(CYS) $(REQS))
 	@python -m pip install -r requirements/dev.in -c requirements/dev.txt
 	@touch .install-deps

Diff for: tools/gen.py

@@ -7,7 +7,7 @@
 import multidict
 
 ROOT = pathlib.Path.cwd()
-while ROOT.parent != ROOT and not (ROOT / ".git").exists():
+while ROOT.parent != ROOT and not (ROOT / "pyproject.toml").exists():
     ROOT = ROOT.parent