chore: update freebsd image

Author: wash2

.cirrus.yml

@@ -1,10 +1,10 @@
 task:
   only_if: $CIRRUS_BRANCH == 'master' || $CIRRUS_PR != ''
   matrix:
-    - name: FreeBSD 13.2
+    - name: FreeBSD 13.4
       freebsd_instance:
-        image_family: freebsd-13-2-snap
- # Install Rust
+        image_family: freebsd-13-4-snap
+  # Install Rust
   setup_script:
     - fetch https://sh.rustup.rs -o rustup.sh
     - sh rustup.sh -y --profile=minimal --default-toolchain stable