Update FreeBSD 11 to 11.4-RELEASE

Author: JohnTitor

.cirrus.yml

@@ -15,7 +15,7 @@ task:
 task:
   name: stable x86_64-unknown-freebsd-11
   freebsd_instance:
-    image: freebsd-11-3-stable-amd64-v20200213
+    image: freebsd-11-4-release-amd64
   setup_script:
     - pkg install -y curl
     - curl https://sh.rustup.rs -sSf --output rustup.sh