src/goTools: update gopls latestVersion to 0.5.1

Change-Id: Ic1e335efb0347d433db884f42e150be3e1ab33a7
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/263982
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>

Author: hyangah

src/goTools.ts

@@ -341,10 +341,10 @@ export const allToolsInformation: { [key: string]: Tool } = {
 		isImportant: false,
 		description: 'Language Server from Google',
 		minimumGoVersion: semver.coerce('1.12'),
-		latestVersion: semver.coerce('0.4.1'),
-		latestVersionTimestamp: moment('2020-05-13', 'YYYY-MM-DD'),
-		latestPrereleaseVersion: semver.coerce('0.4.1'),
-		latestPrereleaseVersionTimestamp: moment('2020-05-13', 'YYYY-MM-DD'),
+		latestVersion: semver.coerce('0.5.1'),
+		latestVersionTimestamp: moment('2020-09-30', 'YYYY-MM-DD'),
+		latestPrereleaseVersion: semver.coerce('0.5.1'),
+		latestPrereleaseVersionTimestamp: moment('2020-09-30', 'YYYY-MM-DD'),
 	},
 	'dlv': {
 		name: 'dlv',