chore: quick fix of integration test (#3339)

## Problem

- invalid profile now returns an error exit code, as fixed in #3304

## Solution

- tell Cheetah to allow that exit code

## Testing

- this **is** a test, run daily on schedule

## Screenshots

No

## Documentation

No

Author: mvidner

service/test/integration/profile_itest.rb

@@ -193,7 +193,7 @@ def web_server_shutdown(server)
 
       it "is evaluated and invalidity reported" do
         stdout, stderr = Cheetah.run("agama", "config", "generate", "-",
-          stdout: :capture, stderr: :capture, stdin: profile_body)
+          stdout: :capture, stderr: :capture, stdin: profile_body, allowed_exitstatus: 1)
         # NOTE: 3 space indent here
         expected = <<~JSON
           {