dashboard: add freebsd-386-12_0

Fixes golang/go#30787

Change-Id: I33d892fe56abcb797c76541fb3b3a12ffe69c598
Reviewed-on: https://go-review.googlesource.com/c/build/+/167199
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Yuval Pavel Zholkover <paulzhol@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/dashboard/builders_test.go b/dashboard/builders_test.go
index 6b4fb37..19f8c5b 100644
--- a/dashboard/builders_test.go
+++ b/dashboard/builders_test.go
@@ -314,6 +314,12 @@
 		{b("freebsd-amd64-11_1@go1.11", "go"), isBuilder},
 		{b("freebsd-amd64-11_1@go1.11", "net@1.11"), isBuilder},
 
+		// FreeBSD 12.0
+		{b("freebsd-amd64-12_0", "go"), both},
+		{b("freebsd-amd64-12_0", "net"), both},
+		{b("freebsd-386-12_0", "go"), onlyPost},
+		{b("freebsd-386-12_0", "net"), onlyPost},
+
 		{b("linux-amd64-nocgo", "mobile"), none},
 
 		// The physical ARM Androids only runs "go":