all: add support for go.work files as go.mod files

This will allow us to add support for the go.work proposal.

Change-Id: I13b374ede724a5a10f0ad11b1073d7849226a4bf
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/341849
Trust: Rebecca Stambler <[email protected]>
Run-TryBot: Rebecca Stambler <[email protected]>
TryBot-Result: kokoro <[email protected]>
Reviewed-by: Hyang-Ah Hana Kim <[email protected]>

Author: stamblerre

package.json

@@ -131,7 +131,8 @@
         "id": "go.mod",
         "extensions": [
           "go.mod",
-          "gopls.mod"
+          "gopls.mod",
+          "go.work"
         ],
         "aliases": [
           "Go Module File"

src/goLanguageServer.ts

@@ -460,7 +460,8 @@ export async function buildLanguageClient(cfg: BuildLanguageClientOption): Promi
 		// gopls handles only file URIs.
 		{ language: 'go', scheme: 'file' },
 		{ language: 'go.mod', scheme: 'file' },
-		{ language: 'go.sum', scheme: 'file' }
+		{ language: 'go.sum', scheme: 'file' },
+		{ language: 'go.work', scheme: 'file' }
 	];
 
 	// Let gopls know about .tmpl - this is experimental, so enable it only in the experimental mode now.