Auto merge of #381 - theduke:patch-1, r=jdm
Auto merge of #381 - theduke:patch-1, r=jdm

Bump heapsize to at least 0.4.1 (relicensed)

Heapsize was released as `0.4.1` to reflect the license change. (https://github.com/servo/heapsize/pull/85).

Fixes https://github.com/servo/rust-url/issues/317.

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servo/rust-url,servo/rust-url