Remove the Cirrus CI for FreeBSD 11, which is no longer supported.

.cirrus.yml

@@ -28,17 +28,3 @@ task:
   test_script:
     - . $HOME/.cargo/env
     - cargo test --features=fs_utf8 --workspace
-
-task:
-  name: stable x86_64-unknown-freebsd-11
-  freebsd_instance:
-    image_family: freebsd-11-4
-  setup_script:
-    - pkg install -y curl
-    - curl https://sh.rustup.rs -sSf --output rustup.sh
-    - sh rustup.sh --default-toolchain stable -y --profile=minimal
-    - . $HOME/.cargo/env
-    - rustup default stable
-  test_script:
-    - . $HOME/.cargo/env
-    - cargo test --features=fs_utf8 --workspace