all: start v1.36.12-devel

Change-Id: Iee80636890078ff00dc85bb30f29bb76b352c859
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/811761
Auto-Submit: Nicolas Hillegeer <aktau@google.com>
Reviewed-by: Nicolas Hillegeer <aktau@google.com>
LUCI-TryBot-Result: golang-scoped@luci-project-accounts.iam.gserviceaccount.com <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

internal/version/version.go

diff --git a/internal/version/version.go b/internal/version/version.go
index 58ff0e2..4ab8def 100644
--- a/internal/version/version.go
+++ b/internal/version/version.go
@@ -53,7 +53,7 @@
 	Major      = 1
 	Minor      = 36
 	Patch      = 12
-	PreRelease = ""
+	PreRelease = "devel"
 )
 
 // String formats the version string for this module in semver format.