Delete unused .cirrus.yml configuration file

The .cirrus.yml file was removed as it is no longer needed for our CI/CD processes. This helps clean up the repository and avoids confusion over unused configurations.

.cirrus.yml

@@ -1,23 +0,0 @@
-# SPDX-FileCopyrightText: 2022 Winni Neessen <winni@neessen.dev>
-#
-# SPDX-License-Identifier: MIT
-
-freebsd_task:
-  name: FreeBSD
-
-  matrix:
-    - name: FreeBSD 13.3
-      freebsd_instance:
-        image_family: freebsd-13-3
-    - name: FreeBSD 14.0
-      freebsd_instance:
-        image_family: freebsd-14-0
-
-  env:
-    TEST_SKIP_SENDMAIL: 1
-
-  pkginstall_script:
-    - pkg install -y go
-
-  test_script:
-    - go test -race -cover -shuffle=on ./...