Auto merge of #12968 - TyanNN:master, r=Ms2ger

Do not define Pipeline::setup_common on Windows

Fixes #12856
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- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #12856.

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- [x] These changes do not require tests because it just removes the compiler warning

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components/constellation/pipeline.rs

@@ -538,6 +538,7 @@ impl UnprivilegedPipelineContent {
         process::exit(1);
     }
 
+    #[cfg(not(windows))]
     fn setup_common<C: CommandMethods>(&self, command: &mut C, token: String) {
         C::arg(command, "--content-process");
         C::arg(command, token);