all: start v1.35.2-devel

Change-Id: I81e537e46e952d593ebd99dd80dad723a064477e
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/627876
Auto-Submit: Michael Stapelberg <stapelberg@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Stapelberg <stapelberg@google.com>
diff --git a/internal/version/version.go b/internal/version/version.go
index 62a52a4..3eac180 100644
--- a/internal/version/version.go
+++ b/internal/version/version.go
@@ -53,7 +53,7 @@
 	Major      = 1
 	Minor      = 35
 	Patch      = 2
-	PreRelease = ""
+	PreRelease = "devel"
 )
 
 // String formats the version string for this module in semver format.