Feature: Support closing dialog windows (#233)

Supports closing dialogs in development. Upgrades gas-client to 1.2.0 and uses new API here: Add scriptHostFunctions for google.script.host gas-client#36
Example button to close dialog in Bootstrap sample
Updates integration tests

package.json

@@ -1,6 +1,6 @@
 {
   "name": "react-google-apps-script",
-  "version": "3.0.0",
+  "version": "3.1.0",
   "type": "module",
   "description": "Starter project for using React with Google Apps Script",
   "repository": {
@@ -41,7 +41,7 @@
     "@emotion/react": "^11.10.6",
     "@emotion/styled": "^11.10.6",
     "@mui/material": "^5.11.11",
-    "gas-client": "^1.1.1",
+    "gas-client": "^1.2.0",
     "prop-types": "^15.8.1",
     "react": "^18.2.0",
     "react-bootstrap": "^2.4.0",