devapp: update burndown chart to track 1.17 milestone

Change-Id: I28df5ed9a2a013b87a6d5c03ee12869d95ea9d07
Reviewed-on: https://go-review.googlesource.com/c/build/+/295191
Run-TryBot: Dan Peterson <danp@danp.net>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Trust: Jeremy Faller <jeremy@golang.org>
diff --git a/devapp/release.go b/devapp/release.go
index 28defc7..ec6081b 100644
--- a/devapp/release.go
+++ b/devapp/release.go
@@ -27,11 +27,11 @@
 	prefixDev      = "[dev."
 
 	// The title of the current release milestone in GitHub.
-	curMilestoneTitle = "Go1.16"
+	curMilestoneTitle = "Go1.17"
 )
 
 // The start date of the current release milestone.
-var curMilestoneStart = time.Date(2020, 8, 12, 0, 0, 0, 0, time.UTC)
+var curMilestoneStart = time.Date(2021, 2, 22, 0, 0, 0, 0, time.UTC)
 
 // titleDirs returns a slice of prefix directories contained in a title. For
 // devapp,maintner: my cool new change, it will return ["devapp", "maintner"].