update workbench extension version number (#5214)

Bump the Workbench extension version to 1.5.13 to match upstream.
Normally this will be updated by the upstream merge, but since that
process is on hold I'm updating the number manually so we can do some
testing.

### QA Notes
This will be tested on the Workbench side. FYI @Trevor-Reid

product.json

@@ -223,10 +223,10 @@
 		},
 		{
 			"name": "rstudio.rstudio-workbench",
-			"version": "1.5.7",
+			"version": "1.5.13",
 			"s3Bucket": "rsw-vscode-extension",
 			"type": "reh-web",
-			"sha256": "9ac536b65c91fd86274fe2cbb2ea2c381e13ba309027044bc98438730c4fa66c",
+			"sha256": "bfa920d48646f4828f83dc2dbc553e12c5871d6cd75182a0427ef3db4364733f",
 			"metadata": {
 				"publisherDisplayName": "Posit PBC"
 			}