Fixed Office365 tool __init__.py files, tests, and get_tools() function (#7046)

## Description
Added Office365 tool modules to `__init__.py` files
## Issue
As described in Issue
https://github.com/hwchase17/langchain/issues/6936, the Office365
toolkit can't be loaded easily because it is not included in the
`__init__.py` files.
## Reviewer
@dev2049

tests/unit_tests/tools/test_public_api.py

@@ -55,6 +55,12 @@ _EXPECTED = [
     "MoveFileTool",
     "NavigateBackTool",
     "NavigateTool",
+    "O365SearchEmails",
+    "O365SearchEvents",
+    "O365CreateDraftMessage",
+    "O365SendMessage",
+    "O365SendEvent",
+    "authenticate",
     "OpenAPISpec",
     "OpenWeatherMapQueryRun",
     "PubmedQueryRun",

tests/unit_tests/tools/test_signatures.py

@@ -9,11 +9,16 @@ import pytest
 
 from langchain.tools.base import BaseTool
 from langchain.tools.gmail.base import GmailBaseTool
+from langchain.tools.office365.base import O365BaseTool
 from langchain.tools.playwright.base import BaseBrowserTool
 
 
 def get_non_abstract_subclasses(cls: Type[BaseTool]) -> List[Type[BaseTool]]:
-    to_skip = {BaseBrowserTool, GmailBaseTool}  # Abstract but not recognized
+    to_skip = {
+        BaseBrowserTool,
+        GmailBaseTool,
+        O365BaseTool,
+    }  # Abstract but not recognized
     subclasses = []
     for subclass in cls.__subclasses__():
         if (