[release] package.json: v0.28.1

Update version string for release

Change-Id: I06bdbd26e6623bfb22a062264b7f3d1d90e6ca47
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/352053
Trust: Hyang-Ah Hana Kim <hyangah@gmail.com>
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
TryBot-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Suzy Mueller <suzmue@golang.org>

package-lock.json

diff --git a/package-lock.json b/package-lock.json
index d213729..f83d3a7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "go",
-  "version": "0.28.0",
+  "version": "0.28.1",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "go",
-      "version": "0.28.0",
+      "version": "0.28.1",
       "license": "MIT",
       "dependencies": {
         "deep-equal": "^2.0.2",

package.json

diff --git a/package.json b/package.json
index 0f406cb..8a7e8d7 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "go",
   "displayName": "Go",
-  "version": "0.28.0",
+  "version": "0.28.1",
   "publisher": "golang",
   "description": "Rich Go language support for Visual Studio Code",
   "author": {