MQE-1963: Update XSD Schema to verify that file has only single entity

Author: jilu1

docs/guides/git-vs-composer-install.md

@@ -55,6 +55,8 @@ The file structure under both paths is the same:
 │   └── ...
 ├── Section
 │   └── ...
+├── Suite
+│   └── ...
 └── Test
     └── ...
 ```
@@ -65,6 +67,7 @@ With either type of installation, all tests and test data are read and merged by
 
 1. `<magento_root>/app/code/<vendor_name>/<module_name>/Test/Mftf/`
 1. `<magento_root>/vendor/<vendor_name>/<module_name>/Test/Mftf/`
+1. `<magento_root>/dev/tests/acceptance/tests/functional/<vendor_name>/<module_name>/`
 
 ## Conclusion
 

docs/introduction.md

@@ -104,14 +104,14 @@ codeception.dist.yml            // Codeception configuration (generated while ru
 
 ## MFTF tests
 
-The MFTF supports two different locations for storing the tests and test artifacts:
-
+The MFTF supports three different locations for storing the tests and test artifacts:
 -  `<magento_root>/app/code/<vendor_name>/<module_name>/Test/Mftf/` is the directory to create new tests.
 -  `<magento_root>/vendor/<vendor_name>/<module_name>/Test/Mftf/` is the directory with the out of the box tests (fetched by the Composer).
+-  `<magento_root>/dev/tests/acceptance/tests/functional/<vendor_name>/<module_name>/` is the directory to create new tests that depends on more than one Magento modules.
 
 All tests and test data from these locations are merged in the order indicated in the above list.
 
-The file structure under the both path cases is the same:
+The directories immediately follow above three paths use the same format and further sub-directories under each category are supported.
 
 ```tree
 <Path>
@@ -125,6 +125,8 @@ The file structure under the both path cases is the same:
 │   └── ...
 ├── Section
 │   └── ...
+├── Suite
+│   └── ...
 └── Test
     └── ...
 ```