Auto merge of #19413 - servo:jdm-patch-9, r=avadacatavra

Don't confuse Cargo when building dependencies.

It's not totally clear why this is experienced intermittently (see #19402), but this allowed mp4parse-capi to actually build on my machine.

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Cargo.toml

@@ -4,6 +4,7 @@ members = [
     "ports/geckolib",
     "ports/servo",
 ]
+exclude = [".cargo"]
 
 [profile.dev]
 codegen-units = 4