[release] src/goTools: update dlv-dap @v1.6.1-0.20210419181450-2408ed87bf87

https://proxy.golang.org/github.com/go-delve/delve/@v/master.info
{"Version":"v1.6.1-0.20210419181450-2408ed87bf87","Time":"2021-04-19T18:14:50Z"}

That includes substitutePath and shadowed variable support.

Change-Id: I1a8e20ccdf9d9e9fdc39160abb9f042d6a8d194e
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/311453
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

@@ -450,8 +450,8 @@ export const allToolsInformation: { [key: string]: Tool } = {
 		description: 'Go debugger (Delve built for DAP experiment)',
 		defaultVersion: 'master', // Always build from the master.
 		minimumGoVersion: semver.coerce('1.14'), // last 3 versions per delve policy
-		latestVersion: semver.parse('1.6.1-0.20210414072240-747f03788315'),
-		latestVersionTimestamp: moment('2021-04-14', 'YYYY-MM-DD')
+		latestVersion: semver.parse('1.6.1-0.20210419181450-2408ed87bf87'),
+		latestVersionTimestamp: moment('2021-04-19', 'YYYY-MM-DD')
 	},
 	'fillstruct': {
 		name: 'fillstruct',