community: Add document manager and mongo document manager (#17320)

- **Description:** 
    - Add DocumentManager class, which is a nosql record manager. 
- In order to use index and aindex in
libs/langchain/langchain/indexes/_api.py, DocumentManager inherits
RecordManager.
    - Also I added the MongoDB implementation of Document Manager too.
  - **Dependencies:** pymongo, motor
  
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- **Description:** Add DocumentManager class, which is a no sql record
manager. To use index method and aindex method in indexes._api.py,
Document Manager inherits RecordManager.Add the MongoDB implementation
of Document Manager.
  - **Dependencies:** pymongo, motor

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---------

Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>

docker/docker-compose.yml

@@ -1,5 +1,10 @@
 # docker-compose to make it easier to spin up integration tests.
 # Services should use NON standard ports to avoid collision with
+# any existing services that might be used for development.
+# ATTENTION: When adding a service below use a non-standard port
+# increment by one from the preceding port.
+# For credentials always use `langchain` and `langchain` for the
+# username and password. 
 version: "3"
 name: langchain-tests
 
@@ -19,3 +24,11 @@ services:
     image: graphdb
     ports:
       - "6021:7200"
+  mongo:
+    image: mongo:latest
+    container_name: mongo_container
+    ports:
+      - "6022:27017"
+    environment:
+      MONGO_INITDB_ROOT_USERNAME: langchain
+      MONGO_INITDB_ROOT_PASSWORD: langchain