Auto merge of #16088 - mbrubeck:always-be-updating, r=emilio

Update parking_lot_core and smallvec

- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because they update third-party code only

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components/style/Cargo.toml

@@ -49,7 +49,7 @@ serde = {version = "0.9", optional = true}
 serde_derive = {version = "0.9", optional = true}
 servo_atoms = {path = "../atoms", optional = true}
 servo_config = {path = "../config"}
-smallvec = "0.1"
+smallvec = "0.3"
 style_traits = {path = "../style_traits"}
 servo_url = {path = "../url"}
 time = "0.1"