all: start v1.35.0-devel

Change-Id: I094b4192fa383ae40f0d3f11050a570fda07fc15
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/618196
Reviewed-by: Lasse Folger <lassefolger@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
diff --git a/internal/version/version.go b/internal/version/version.go
index fc7077d..fe5b24d 100644
--- a/internal/version/version.go
+++ b/internal/version/version.go
@@ -53,7 +53,7 @@
 	Major      = 1
 	Minor      = 35
 	Patch      = 0
-	PreRelease = ""
+	PreRelease = "devel"
 )
 
 // String formats the version string for this module in semver format.