all: release v1.36.8

Change-Id: I2f43ed2fa35901c020e7ce371586cc0c513876df
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/697361
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Lasse Folger <lassefolger@google.com>

Author: stapelberg

internal/version/version.go

@@ -52,8 +52,8 @@ import (
 const (
 	Major      = 1
 	Minor      = 36
-	Patch      = 7
-	PreRelease = "devel"
+	Patch      = 8
+	PreRelease = ""
 )
 
 // String formats the version string for this module in semver format.