docs: fix httpx conflicts with overrides in docs build (#29180)

.github/workflows/api_doc_build.yml

@@ -72,7 +72,7 @@ jobs:
       - name: Install dependencies
         working-directory: langchain
         run: |
-          python -m uv pip install $(ls ./libs/partners | xargs -I {} echo "./libs/partners/{}")
+          python -m uv pip install $(ls ./libs/partners | xargs -I {} echo "./libs/partners/{}") --overrides ./docs/vercel_overrides.txt
           python -m uv pip install libs/core libs/langchain libs/text-splitters libs/community libs/experimental libs/standard-tests
           python -m uv pip install -r docs/api_reference/requirements.txt
 

docs/Makefile

@@ -27,7 +27,7 @@ install-py-deps:
 	$(PYTHON) -m pip install -q --upgrade pip
 	$(PYTHON) -m pip install -q --upgrade uv
 	$(PYTHON) -m uv pip install -q --pre -r vercel_requirements.txt
-	$(PYTHON) -m uv pip install -q --pre $$($(PYTHON) scripts/partner_deps_list.py)
+	$(PYTHON) -m uv pip install -q --pre $$($(PYTHON) scripts/partner_deps_list.py) --overrides vercel_overrides.txt
 
 generate-files:
 	mkdir -p $(INTERMEDIATE_DIR)

docs/vercel_overrides.txt

@@ -0,0 +1 @@
+httpx