fix makefile help (#8723)

Fixed the `makefile` help. It was not up-to-date.
 @baskaryan

Makefile

@@ -43,7 +43,12 @@ spell_fix:
 
 help:
 	@echo '----'
-	@echo 'coverage                     - run unit tests and generate coverage report'
+	@echo 'clean                        - run docs_clean and api_docs_clean'
 	@echo 'docs_build                   - build the documentation'
 	@echo 'docs_clean                   - clean the documentation build artifacts'
 	@echo 'docs_linkcheck               - run linkchecker on the documentation'
+	@echo 'api_docs_build               - build the API Reference documentation'
+	@echo 'api_docs_clean               - clean the API Reference documentation build artifacts'
+	@echo 'api_docs_linkcheck           - run linkchecker on the API Reference documentation'
+	@echo 'spell_check               	- run codespell on the project'
+	@echo 'spell_fix               		- run codespell on the project and fix the errors'

libs/langchain/Makefile

@@ -92,15 +92,24 @@ spell_fix:
 ######################
 
 help:
-	@echo '----'
-	@echo 'coverage                     - run unit tests and generate coverage report'
+	@echo '===================='
+	@echo '-- DOCUMENTATION --'
+	@echo 'clean                        - run docs_clean and api_docs_clean'
 	@echo 'docs_build                   - build the documentation'
 	@echo 'docs_clean                   - clean the documentation build artifacts'
 	@echo 'docs_linkcheck               - run linkchecker on the documentation'
+	@echo 'api_docs_build               - build the API Reference documentation'
+	@echo 'api_docs_clean               - clean the API Reference documentation build artifacts'
+	@echo 'api_docs_linkcheck           - run linkchecker on the API Reference documentation'
+	@echo '-- LINTING --'
 	@echo 'format                       - run code formatters'
 	@echo 'lint                         - run linters'
+	@echo 'spell_check               	- run codespell on the project'
+	@echo 'spell_fix               		- run codespell on the project and fix the errors'
+	@echo '-- TESTS --'
+	@echo 'coverage                     - run unit tests and generate coverage report'
 	@echo 'test                         - run unit tests'
-	@echo 'tests                        - run unit tests'
+	@echo 'tests                        - run unit tests (alias for "make test")'
 	@echo 'test TEST_FILE=<test_file>   - run all tests in file'
 	@echo 'extended_tests               - run only extended unit tests'
 	@echo 'test_watch                   - run unit tests in watch mode'