Added endpoint for fetching all notebook jobs (#834)

* Added endpoint for fetching all notebook jobs

* Refractored NotebookJobInfo to AgentNotebookInfo to make it more consistent with the rest of the codebase

* Added Notebook History endpoint in contracts.

* Added Create, Update, Delete notebook endpoints. Also added separate fetch template, materialized notebook endpoints. This will make the Notebook Request and Notebook History responses lighter.

* AgentNotebookInfo is now derived from AgentJobInfo

* added fetch noteook history endpoint

* Added fetching materialized notebook endpoint

* Added code for cleaning up the directory

* Added create notebook api

* Added Update and delete notebook job

* Fixed notebook history API

* Added last run info to the script and template folder

* Added execute database feature for notebook Jobs

* SQL commands are now using sqlparameters to prevent
any injection attacks

* Changed rundate and runtime to string to preserve
leading zeros

* integration test for agentnotebooks api

* Made some changes mentioned in PR

* Refactored the code, removed enpoint logic from the notebook handler and
wrote test cases

* changes select statements, fixed a bug in the test job cleanup
and fixed other stuff mentioned in the PR.

* added notebook_error column in notebook history select statement

* Added get template notebook endpoint

test/Microsoft.SqlTools.ServiceLayer.IntegrationTests/Agent/NotebookResources/testNotebook.ipynb

@@ -0,0 +1,24 @@
+{
+    "metadata": {
+        "kernelspec": {
+            "name": "SQL",
+            "display_name": "SQL",
+            "language": "sql"
+        },
+        "language_info": {
+            "name": "sql",
+            "version": ""
+        }
+    },
+    "nbformat_minor": 2,
+    "nbformat": 4,
+    "cells": [
+        {
+            "cell_type": "code",
+            "source": "select * from sys.all_objects",
+            "metadata": {},
+            "outputs": [],
+            "execution_count": 2
+        }
+    ]
+}