Update document_loader.ipynb (#101)

1. Moved "instance id", "database", and "table" values initiation after the "Automatically restart kernel after installs" cell to retain variable values after restart.

2. Adding missing - sign to package install code

3. Set-up GOOGLE_CLOUD_PROJECT env variable, it is needed in the document loader function

Author: vmanghnani

docs/document_loader.ipynb

@@ -28,22 +28,9 @@
     "* [Create a Spanner instance](https://cloud.google.com/spanner/docs/create-manage-instances)\n",
     "* [Create a Spanner database](https://cloud.google.com/spanner/docs/create-manage-databases)\n",
     "* [Create a Spanner table](https://cloud.google.com/spanner/docs/create-query-database-console#create-schema)\n",
-    "\n",
-    "After confirmed access to database in the runtime environment of this notebook, filling the following values and run the cell before running example scripts."
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "# @markdown Please specify an instance id, a database, and a table for demo purpose.\n",
-    "INSTANCE_ID = \"test_instance\"  # @param {type:\"string\"}\n",
-    "DATABASE_ID = \"test_database\"  # @param {type:\"string\"}\n",
-    "TABLE_NAME = \"test_table\"  # @param {type:\"string\"}"
+    "\n"
    ]
-  },
+  },  
   {
    "cell_type": "markdown",
    "metadata": {},
@@ -61,7 +48,7 @@
    },
    "outputs": [],
    "source": [
-    "%pip install -upgrade --quiet langchain-google-spanner langchain"
+    "%pip install --upgrade --quiet langchain-google-spanner langchain"
    ]
   },
   {
@@ -84,6 +71,25 @@
     "# app.kernel.do_shutdown(True)"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "After confirmed access to database in the runtime environment of this notebook, filling the following values and run the cell before running example scripts."
+   ]
+  },
+  {
+    "cell_type": "code",
+    "execution_count": null,
+    "metadata": {},
+    "outputs": [],
+    "source": [
+     "# @markdown Please specify an instance id, a database, and a table for demo purpose.\n",
+     "INSTANCE_ID = \"test_instance\"  # @param {type:\"string\"}\n",
+     "DATABASE_ID = \"test_database\"  # @param {type:\"string\"}\n",
+     "TABLE_NAME = \"test_table\"  # @param {type:\"string\"}"
+    ]
+   },
   {
    "cell_type": "markdown",
    "metadata": {},
@@ -109,7 +115,8 @@
     "PROJECT_ID = \"my-project-id\"  # @param {type:\"string\"}\n",
     "\n",
     "# Set the project id\n",
-    "!gcloud config set project {PROJECT_ID}"
+    "!gcloud config set project {PROJECT_ID}\n",
+    "%env GOOGLE_CLOUD_PROJECT={PROJECT_ID}"
    ]
   },
   {